CVE-2025-8735: GNU cflow · NULL Pointer Dereference
Affects GNU cflowSource CVE Database V5
Not known to be exploited · CVSS 4.8 Medium.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 8 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
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), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| GNU cflow | Affected
| Fixed in– |
AI-suggested
To mitigate CVE-2025-8735, European organizations should first inventory all systems running GNU cflow versions 1.0 through 1.8 and assess their exposure. Since no official patches are currently linked, organizations should monitor GNU project repositories and security advisories for updates addressing this vulnerability. In the interim, restricting local access to trusted personnel only will reduce the risk of exploitation. Implementing strict access controls and user permissions on development and build servers can prevent unprivileged users from triggering the vulnerability. Where feasible, replacing GNU cflow with alternative static analysis tools not affected by this issue can be considered. Additionally, integrating runtime monitoring to detect abnormal process crashes or unusual behavior in build environments can provide early warning of exploitation attempts. For organizations with in-house development capabilities, reviewing and patching the vulnerable yylex function in the c.c source code may be an option. Finally, educating developers and system administrators about the vulnerability and safe handling of local access rights will strengthen overall security posture.
Description
A vulnerability classified as problematic was found in GNU cflow up to 1.8. Affected by this vulnerability is the function yylex of the file c.c of the component Lexer. The manipulation leads to null pointer dereference. An attack has to be approached locally. The exploit has been disclosed to the public and may be used.
References
- vuldb.com (opens in a new tab)
- vuldb.com (opens in a new tab)
- vuldb.com (opens in a new tab)
- lists.gnu.org/archive/html/bug-cflow/2025-07/msg00000.html (opens in a new tab)
- drive.google.com/file/d/1Q_rDQSEl3cBu6SUbfqr9pV9cHgvKcXFI/view?usp=drive_link (opens in a new tab)
- gnu.org (opens in a new tab)
- openwall.com/lists/oss-security/2025/10/27/12 (opens in a new tab)