Vulnerability-Lookup

GHSA-QG92-VXJM-X4Q9

Vulnerability from github – Published: 2026-06-09 18:31 – Updated: 2026-06-09 18:31

Details

Hermes WebUI before version 0.51.303 contains a time-of-check time-of-use (TOCTOU) race condition vulnerability in the git_discard function within api/workspace_git.py that allows attackers to delete files outside the configured workspace boundary by replacing a validated path component with a symlink after validation but before deletion. Attackers can substitute a workspace-controlled path component with a symlink pointing to an external directory between the safe_resolve_ws() validation step and the subsequent Path.unlink() or shutil.rmtree() deletion call, causing the delete operation to follow the symlink and remove arbitrary files outside the workspace.

Severity

5.0 (Medium)


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

4.3 (Medium)


                  
                    CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:A/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-49958"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-367"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-09T17:17:49Z",
    "severity": "MODERATE"
  },
  "details": "Hermes WebUI before version 0.51.303 contains a time-of-check time-of-use (TOCTOU) race condition vulnerability in the git_discard function within api/workspace_git.py that allows attackers to delete files outside the configured workspace boundary by replacing a validated path component with a symlink after validation but before deletion. Attackers can substitute a workspace-controlled path component with a symlink pointing to an external directory between the safe_resolve_ws() validation step and the subsequent Path.unlink() or shutil.rmtree() deletion call, causing the delete operation to follow the symlink and remove arbitrary files outside the workspace.",
  "id": "GHSA-qg92-vxjm-x4q9",
  "modified": "2026-06-09T18:31:01Z",
  "published": "2026-06-09T18:31:01Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49958"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/pull/3702"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/pull/3756"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/commit/4580f584964d640b95c4ffc9245a21ab926bec73"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nesquena/hermes-webui/releases/tag/v0.51.303"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/hermes-webui-toctou-race-condition-via-git-discard"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:A/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-49958 (GCVE-0-2026-49958)

Vulnerability from cvelistv5 – Published: 2026-06-09 16:35 – Updated: 2026-06-09 18:26 X_Open Source

Title

Hermes WebUI < 0.51.303 TOCTOU Race Condition via git_discard

Summary

Severity

4.3 (Medium)


                        
                          CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:A/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

Assigner

VulnCheck

References

5 references

URL	Tags
https://github.com/nesquena/hermes-webui/releases…	release-notes
https://github.com/nesquena/hermes-webui/pull/3702	technical-description
https://github.com/nesquena/hermes-webui/pull/3756	issue-tracking
https://github.com/nesquena/hermes-webui/commit/4…	patch
https://www.vulncheck.com/advisories/hermes-webui…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
nesquena	hermes-webui	Affected: 0 , < 0.51.303 (semver)

Date Public

2026-06-06 00:00

Credits

Chia Min Jun Lennon

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-49958",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-09T18:26:30.104471Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-06-09T18:26:54.848Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/nesquena/hermes-webui/pull/3702"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "hermes-webui",
          "repo": "https://github.com/nesquena/hermes-webui",
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              "lessThan": "0.51.303",
              "status": "affected",
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            }
          ]
        }
      ],
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      "descriptions": [
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            "Recovery": "NOT_DEFINED",
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    "datePublished": "2026-06-09T16:35:42.411Z",
    "dateReserved": "2026-06-02T16:30:15.233Z",
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}

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.

Action not permitted

GHSA-QG92-VXJM-X4Q9

CVE-2026-49958 (GCVE-0-2026-49958)

Tags

Sightings

Nomenclature