TOCTOU with root privilege in ad_flush

published 2026-05-21 5 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-31245

cvss: 3.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits: 0; none known

A time-of-check time-of-use (TOCTOU) condition in the ad_flush function in Netatalk 3.0.0 through 4.4.2 involves root-privileged file operations, which may allow a remote attacker to cause limited data modification under specific race conditions.

Patch / fix

fixed in 1 distros 2

Netatalk Netatalk 4.5.0

debian alpine

netatalk Debian 14 4.5.0~ds-1

debian advisories DEBIAN-CVE-2026-7837

netatalk Alpine 3.24 4.5.0-r0

alpine advisories ALPINE-CVE-2026-7837

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-7837 updated 2026-06-28 cvss 3.7

netatalk: Netatalk: Limited data modification due to TOCTOU condition

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 5 mo ago (2026-05-21)

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.7	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected products

Netatalk Netatalk

Classification

Weakness

CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

References

netatalk.io /security/CVE-2026-7837
vendor-advisory

Sources

CVE List CVE-2026-7837
NVD CVE-2026-7837

Fencer Vulns 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.

Summary