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Vulnerability from cleanstart
Published
2026-09-01 11:17
Modified
2026-09-02 06:40
Summary
Security fixes in langfuse-worker 3.224.1-r2
Details
Package langfuse-worker version 3.224.1-r2 fixes 4 vulnerabilities: CVE-2026-14257, CVE-2026-69152, ghsa-r28c-9q8g-f849, CVE-2026-69153
References
| URL | Type | |
|---|---|---|
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CVE-2026-14257 (GCVE-0-2026-14257)
Vulnerability from cvelistv5 – Published: 2026-07-23 12:54 – Updated: 2026-07-23 14:44
VLAI
EPSS
VEX
Title
brace-expansion DoS via unbounded expansion length causing an out-of-memory process crash
Summary
brace-expansion through 5.0.7 is vulnerable to denial of service via memory exhaustion. The expand() function limits the number of results with a max option (default 100,000) but does not bound the length of each result string. By chaining multiple brace groups, an attacker keeps the result count under the limit while making each result progressively longer, so total memory scales with both count and string length until the process hits a fatal, uncatchable out-of-memory error. About 7.5 KB of input ('{a,b}'.repeat(1500)) crashes a default Node.js process. Any application that passes attacker-influenced strings to brace-expansion.expand() - directly or transitively via minimatch / glob brace patterns - can be crashed by a small request. Fixed in 5.0.8 by adding a maxLength option (default 4,000,000) that bounds accumulated output and intermediate arrays.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-23 14:44 UTC
CWE
Assigner
References
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| juliangruber | brace-expansion |
Affected:
0 , ≤ 5.0.7
(semver)
|
Credits
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CVE-2026-69152 (GCVE-0-2026-69152)
Vulnerability from cvelistv5 – Published: 2026-08-03 16:33 – Updated: 2026-08-03 20:12
VLAI
EPSS
VEX
Title
brace-expansion: DoS via unbounded intermediate arrays, bypassing the CVE-2026-14257 mitigation
Summary
The brace-expansion library generates arbitrary strings containing a common prefix and suffix. Prior to 1.1.18, 2.1.4, 3.0.6, and 5.0.9, expand() does not apply maxLength while constructing comma-alternative intermediate arrays or padded sequences, allowing attacker-controlled input to exhaust memory or block the event loop. The fix for CVE-2026-14257 is bypassed by the vulnerability. This issue is fixed in versions 1.1.18, 2.1.4, 3.0.6, and 5.0.9.
Severity
7.5 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 20:11 UTC
CWE
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/juliangruber/brace-expansion/s… | x_refsource_CONFIRM |
| https://github.com/juliangruber/brace-expansion/c… | x_refsource_MISC |
| https://github.com/juliangruber/brace-expansion/c… | x_refsource_MISC |
| https://github.com/juliangruber/brace-expansion/c… | x_refsource_MISC |
| https://github.com/juliangruber/brace-expansion/c… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| juliangruber | brace-expansion |
Affected:
< 1.1.18
Affected: >= 2.0.0, < 2.1.4 Affected: >= 3.0.0, < 3.0.6 Affected: >= 4.0.0, < 5.0.9 |
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CVE-2026-69153 (GCVE-0-2026-69153)
Vulnerability from cvelistv5 – Published: 2026-08-03 16:56 – Updated: 2026-08-03 18:28
VLAI
EPSS
VEX
Title
PostCSS: incomplete fix of CVE-2026-45623 — attacker-controlled sourceMappingURL reads arbitrary .map files when `from` is unset
Summary
PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Prior to 8.5.19, if from is unset, an attacker can cause PreviousMap.loadFile() to read an unintended source-map file by supplying an absolute or directory-traversal sourceMappingURL. The resulting map’s sources and sourcesContent may then be exposed to the application. This issue is fixed in version 8.5.19.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-03 18:28 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/postcss/postcss/security/advis… | x_refsource_CONFIRM |
| https://github.com/postcss/postcss/commit/7beca13… | x_refsource_MISC |
| https://github.com/postcss/postcss/releases/tag/8.5.19 | x_refsource_MISC |
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GHSA-R28C-9Q8G-F849
Vulnerability from github – Published: 2026-07-24 16:24 – Updated: 2026-08-13 17:55
VLAI
Summary
PostCSS: Path Traversal in Previous Source Map Auto-Loading (sourceMappingURL) leads to Arbitrary .map File Disclosure
Details
Vulnerability Details
File: lib/previous-map.js
Line: 87-98 (loadFile), 129-144 (loadMap)
Root Cause
PostCSS auto-detects a /*# sourceMappingURL=... */ comment inside the CSS text it is asked to parse and, unless the caller explicitly passes map: false, attempts to load that path from disk as a "previous source map." This happens on every postcss.parse() / postcss().process() call by default (opt-out, not opt-in).
loadMap() builds the candidate path via join(dirname(opts.from), annotation), where annotation is the raw, attacker-controlled string from the CSS comment. path.join() normalizes but does not sandbox .. segments, so a ../../../ prefix walks the resolved path outside the intended directory. If opts.from is not set at all, the annotation is used completely unmodified — an absolute path in the CSS comment is read verbatim.
8.5.12 already fixed a strictly worse variant of this (any file, any extension, could be read) by requiring the resolved path to end in .map (loadFile()). That fix did not address the traversal itself, only the target extension. Since the join(dirname(file), map) logic has existed unchanged since PostCSS 8.0.0 (Feb 2020), any file ending in .map remains readable through this path in the current release (8.5.16).
Once loaded, MapGenerator.isMap() treats the mere presence of a loaded "previous map" as an implicit request to generate result.map, even when the caller never set the map option. If the loaded map has a sourcesContent field (common for maps emitted by bundlers/transpilers), that content is merged into result.map and returned to the caller — disclosing the traversed-to file's content to whoever supplied the CSS.
Attack Scenario
- A service accepts user-submitted CSS and runs it through PostCSS to lint/format/transform it, e.g.
postcss().process(userCss, { from: '/app/uploads/user123/input.css', to: '/app/uploads/user123/output.css' })— idiomatic usage;mapoption untouched. - Attacker submits CSS containing
/*# sourceMappingURL=../../../../some/other/app/dist/bundle.js.map */(or an absolute path iffromis unset). - PostCSS reads that
.mapfile and folds itssourcesContentintoresult.map. - The service does what most build pipelines do with a truthy
result.map— writes it next to the CSS output or returns it via API (source maps are meant to be consumed by browser devtools, so this is commonly public/served). - Attacker retrieves the emitted map and reads out the traversed file's content.
Impact
Disclosure of the contents of arbitrary .map files reachable via path traversal (or absolute path when from is unset) from the process's filesystem. Affects any application processing CSS it does not fully trust without explicitly passing map: false. No authentication or user interaction beyond submitting CSS text is required.
Vulnerable Code
loadFile(path, cssFile, trusted) {
if (!trusted && !this.unsafeMap) {
if (!/\.map$/i.test(path)) {
return undefined
}
}
this.root = dirname(path)
if (existsSync(path)) {
this.mapFile = path
return readFileSync(path, 'utf-8').toString().trim()
}
}
loadMap(file, prev) {
...
} else if (this.annotation) {
let map = this.annotation
if (file) map = join(dirname(file), map)
let unknown = this.loadFile(map, file, false)
...
}
}
Recommended Fix
Constrain the resolved path to remain inside the CSS file's own directory instead of relying solely on a filename-extension check:
loadFile(path, cssFile, trusted) {
if (!trusted && !this.unsafeMap) {
if (!/\.map$/i.test(path)) {
return undefined
}
if (!cssFile) return undefined
let root = resolve(dirname(cssFile))
let resolvedPath = resolve(root, path)
if (resolvedPath !== root && !resolvedPath.startsWith(root + sep)) {
return undefined
}
}
this.root = dirname(path)
if (existsSync(path)) {
this.mapFile = path
return readFileSync(path, 'utf-8').toString().trim()
}
}
I've implemented, tested (full existing test suite — 660/660 passing, plus new PoC-based regression checks for both the traversal and legitimate same-directory cases), and can share this fix on request or via a private fork if invited.
Verification
Dynamically confirmed on v8.5.16 (current npm release / repo HEAD) via a standalone Node.js harness against lib/postcss.js: a "secret" .map file placed two directories outside a simulated project directory was read via a crafted sourceMappingURL comment in otherwise-innocuous CSS, with its sourcesContent appearing verbatim in result.map.toString() — with no map option set by the caller. A second harness confirmed the simpler no-from case reads an absolute path directly. A third harness confirmed map: false is the only current workaround. The attached fix branch closes both vectors while keeping all 660 existing unit tests green.
Severity
7.5 (High)
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 8.5.17"
},
"package": {
"ecosystem": "npm",
"name": "postcss"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "8.5.18"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-73646"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-24T16:24:55Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "## Vulnerability Details\n\n**File**: `lib/previous-map.js`\n**Line**: 87-98 (`loadFile`), 129-144 (`loadMap`)\n\n\n### Root Cause\nPostCSS auto-detects a `/*# sourceMappingURL=... */` comment inside the CSS text it is asked to parse and, unless the caller explicitly passes `map: false`, attempts to load that path from disk as a \"previous source map.\" This happens on every `postcss.parse()` / `postcss().process()` call by default (opt-out, not opt-in).\n\n`loadMap()` builds the candidate path via `join(dirname(opts.from), annotation)`, where `annotation` is the raw, attacker-controlled string from the CSS comment. `path.join()` normalizes but does not sandbox `..` segments, so a `../../../` prefix walks the resolved path outside the intended directory. If `opts.from` is not set at all, the annotation is used completely unmodified \u2014 an absolute path in the CSS comment is read verbatim.\n\n8.5.12 already fixed a strictly worse variant of this (any file, any extension, could be read) by requiring the resolved path to end in `.map` (`loadFile()`). That fix did not address the traversal itself, only the target extension. Since the `join(dirname(file), map)` logic has existed unchanged since PostCSS 8.0.0 (Feb 2020), any file ending in `.map` remains readable through this path in the current release (8.5.16).\n\nOnce loaded, `MapGenerator.isMap()` treats the mere presence of a loaded \"previous map\" as an implicit request to generate `result.map`, even when the caller never set the `map` option. If the loaded map has a `sourcesContent` field (common for maps emitted by bundlers/transpilers), that content is merged into `result.map` and returned to the caller \u2014 disclosing the traversed-to file\u0027s content to whoever supplied the CSS.\n\n### Attack Scenario\n1. A service accepts user-submitted CSS and runs it through PostCSS to lint/format/transform it, e.g. `postcss().process(userCss, { from: \u0027/app/uploads/user123/input.css\u0027, to: \u0027/app/uploads/user123/output.css\u0027 })` \u2014 idiomatic usage; `map` option untouched.\n2. Attacker submits CSS containing `/*# sourceMappingURL=../../../../some/other/app/dist/bundle.js.map */` (or an absolute path if `from` is unset).\n3. PostCSS reads that `.map` file and folds its `sourcesContent` into `result.map`.\n4. The service does what most build pipelines do with a truthy `result.map` \u2014 writes it next to the CSS output or returns it via API (source maps are meant to be consumed by browser devtools, so this is commonly public/served).\n5. Attacker retrieves the emitted map and reads out the traversed file\u0027s content.\n\n### Impact\nDisclosure of the contents of arbitrary `.map` files reachable via path traversal (or absolute path when `from` is unset) from the process\u0027s filesystem. Affects any application processing CSS it does not fully trust without explicitly passing `map: false`. No authentication or user interaction beyond submitting CSS text is required.\n\n### Vulnerable Code\n```js\nloadFile(path, cssFile, trusted) {\n if (!trusted \u0026\u0026 !this.unsafeMap) {\n if (!/\\.map$/i.test(path)) {\n return undefined\n }\n }\n this.root = dirname(path)\n if (existsSync(path)) {\n this.mapFile = path\n return readFileSync(path, \u0027utf-8\u0027).toString().trim()\n }\n}\n\nloadMap(file, prev) {\n ...\n } else if (this.annotation) {\n let map = this.annotation\n if (file) map = join(dirname(file), map)\n let unknown = this.loadFile(map, file, false)\n ...\n }\n}\n```\n\n### Recommended Fix\nConstrain the resolved path to remain inside the CSS file\u0027s own directory instead of relying solely on a filename-extension check:\n```js\nloadFile(path, cssFile, trusted) {\n if (!trusted \u0026\u0026 !this.unsafeMap) {\n if (!/\\.map$/i.test(path)) {\n return undefined\n }\n if (!cssFile) return undefined\n let root = resolve(dirname(cssFile))\n let resolvedPath = resolve(root, path)\n if (resolvedPath !== root \u0026\u0026 !resolvedPath.startsWith(root + sep)) {\n return undefined\n }\n }\n this.root = dirname(path)\n if (existsSync(path)) {\n this.mapFile = path\n return readFileSync(path, \u0027utf-8\u0027).toString().trim()\n }\n}\n```\nI\u0027ve implemented, tested (full existing test suite \u2014 660/660 passing, plus new PoC-based regression checks for both the traversal and legitimate same-directory cases), and can share this fix on request or via a private fork if invited.\n\n### Verification\nDynamically confirmed on v8.5.16 (current npm release / repo HEAD) via a standalone Node.js harness against `lib/postcss.js`: a \"secret\" `.map` file placed two directories outside a simulated project directory was read via a crafted `sourceMappingURL` comment in otherwise-innocuous CSS, with its `sourcesContent` appearing verbatim in `result.map.toString()` \u2014 with no `map` option set by the caller. A second harness confirmed the simpler no-`from` case reads an absolute path directly. A third harness confirmed `map: false` is the only current workaround. The attached fix branch closes both vectors while keeping all 660 existing unit tests green.",
"id": "GHSA-r28c-9q8g-f849",
"modified": "2026-08-13T17:55:54Z",
"published": "2026-07-24T16:24:55Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/postcss/postcss/security/advisories/GHSA-r28c-9q8g-f849"
},
{
"type": "WEB",
"url": "https://github.com/postcss/postcss/commit/95663d3eb7ba26f4854dd19d3b4f4425760cf56c"
},
{
"type": "PACKAGE",
"url": "https://github.com/postcss/postcss"
},
{
"type": "WEB",
"url": "https://github.com/postcss/postcss/releases/tag/8.5.18"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "PostCSS: Path Traversal in Previous Source Map Auto-Loading (sourceMappingURL) leads to Arbitrary .map File Disclosure"
}
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Trend slope:
-
(linear fit over daily sighting counts)
Show additional events:
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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