CVE-2026-8357: The Document Foundation LibreOffice · Out-of-bounds Write
Affects The Document Foundation LibreOfficeSource CVE Database V5
Public exploit available · CVSS 5.4 Medium.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 15 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| The Document FoundationLibreOffice | Affected
| Fixed in– |
Debiandebian/libreofficepkg:deb/debian/libreofficeOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A security update fixing this vulnerability is available from Red Hat for LibreOffice packages in Red Hat Enterprise Linux 7 Extended Life Cycle Support. Users should apply the official Red Hat patch as described in the advisory at https://access.redhat.com/articles/11258. Patch status is confirmed by the vendor advisory. No additional mitigation steps are indicated.
Description
LibreOffice Calc compiles cell formulas when opening a spreadsheet. A heap buffer overflow existed when compiling a very long formula made up of many opening tokens. The array that tracks nesting depth was allocated one element too small for that worst case, so such a formula wrote one element past its end. In fixed versions the array is sized to hold the largest possible nesting.
References
- libreoffice.org/about-us/security/advisories/cve-2026-8357 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-8357 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2488964 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8357.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:46386 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:35839 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:46387 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43461 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43460 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43423 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43424 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43425 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36832 (opens in a new tab)