CVE-2026-109765
CVSS: 4.2v3.1MediumDeferred
AliasesDEBIAN-CVE-2026-109765
Published 2026-10-13Last modified 2026-10-13
Vulnerability summary
CVSS score
4.2/10
010
Medium · v3.1 (CVE.org)EPSS score
0.17%
0%100%
Low · Change unavailableKEVNot listed0 of 3 catalogs
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 2026-10-13PublishedVulnerability first disclosed.
- 2026-10-13Last modifiedVulnerability information updated.
Description
Race condition, use-after-free in the Graphics: Text component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
CVSS metrics
3 scores · 3 sources · 1 versionMedium 4.2Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:NSourcesAll 3 agree
- NVDNIST4.2MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
- OSV · DebianEcosystem advisory · calculated4.2MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
EPSS trend
Probability
0.17%
Chance of exploitation in the next 30 days
Percentile
6%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
2026-10-142026-10-15
EPSS score0.17%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
- CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Affected systems
Debian2 products
- firefox-esrAll versions (No fix recorded) | < 153.5.0esr-1~deb12u1 | < 153.5.0esr-1~deb13u1
- thunderbirdAll versions (No fix recorded)
1 vendor · 2 products
