Skip to content
Fencer Intel
medium 5.3

CVE-2025-8842 json

NASM Netwide Assember preproc.c do_directive use after free

published last yr. modified 4mo ago also EUVD-2025-24140

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits
0
none known

Summary

A vulnerability has been found in NASM Netwide Assember 2.17rc0. Affected by this issue is the function do_directive of the file preproc.c. The manipulation leads to use after free. An attack has to be approached locally. The exploit has been disclosed to the public and may be used.

Is CVE-2025-8842 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • vuldb.com https://vuldb.com/?submit.623184 referenced PoC, tagged "exploit" by a source, unverified
  • bugzilla.nasm.us https://bugzilla.nasm.us/show_bug.cgi?id=3392933 referenced PoC, tagged "exploit" by a source, unverified
  • drive.google.com https://drive.google.com/file/d/11vEV1vMHXO4BrDGhvWAMm0Qo1woiUwVV/view?usp=drive_link referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 4.8 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA 3.1 5.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 3.0 5.3 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 2.0 4.3 AV:L/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA 4.0 1.9 CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA 3.1 5.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA 2.0 4.3 AV:L/AC:L/Au:S/C:P/I:P/A:P

Affected products

  • NASM Netwide Assember

Classification

Weakness
  • CWE-416 Use After Free
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.