SARA / Free Tools / CVE / CVE-2023-4578

CVE-2023-4578 — When calling `JS::CheckRegExpSyntax` a Syntax Error could have been set which wo

When calling `JS::CheckRegExpSyntax` a Syntax Error could have been set which would end in calling `convertToRuntimeErrorAndClear`. A path in the function could attempt to allocate memory when none is available which would have caused a newly created Out of Memory exception to be

CVSS
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EPSS
0.15% (top 64.50%)
CWE
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Published
2023-09-11T08:01:17.333Z
Last modified
2025-12-18T15:23:11.916Z
CVSS vector
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01What is this vulnerability?

When calling `JS::CheckRegExpSyntax` a Syntax Error could have been set which would end in calling `convertToRuntimeErrorAndClear`. A path in the function could attempt to allocate memory when none is available which would have caused a newly created Out of Memory exception to be mishandled as a Syntax Error. This vulnerability affects Firefox < 117, Firefox ESR < 115.2, and Thunderbird < 115.2.

02Affected products

VendorProductVersions
MozillaFirefoxunspecified
MozillaFirefox ESRunspecified
MozillaThunderbirdunspecified

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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