SARA / Free Tools / CVE / CVE-2023-6858

CVE-2023-6858 — Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to ins

Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to insufficient OOM handling. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.

CVSS
— —
EPSS
0.45% (top 36.50%)
CWE
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Published
2023-12-19T13:38:38.757Z
Last modified
2025-05-07T20:25:21.051Z
CVSS vector
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01What is this vulnerability?

Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to insufficient OOM handling. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.

02Affected products

VendorProductVersions
MozillaFirefox ESRunspecified
MozillaThunderbirdunspecified
MozillaFirefoxunspecified

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

09References

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