CVE-2026-33877: apostrophecms apostrophe · Timing Side Channel
Affects apostrophecms apostropheSource CVE Database V5
Not known to be exploited · CVSS 3.7 Low : upgrade to 4.29.0 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 30% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.29.0
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 15 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 29 Oct 2026.
What to do
Upgrade apostrophecms apostrophe to 4.29.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| apostrophecmsapostrophe | Affected
| Fixed in
|
AI-suggested
This vulnerability has been fixed in ApostropheCMS version 4.29.0. Users should upgrade to version 4.29.0 or later to remediate the issue. Instances that do not have the passwordReset option enabled are not affected. There is no indication of official patches outside of upgrading. Patch status is not explicitly stated beyond the fixed version, so users should consult the vendor's release notes for confirmation.
Description
ApostropheCMS is an open-source Node.js content management system. Versions 4.28.0 and prior contain a timing side-channel vulnerability in the password reset endpoint (/api/v1/@apostrophecms/login/reset-request) that allows unauthenticated username and email enumeration. When a user is not found, the handler returns after a fixed 2-second artificial delay, but when a valid user is found, it performs a MongoDB update and SMTP email send with no equivalent delay normalization, producing measurably different response times. The endpoint also accepts both username and email via an $or query, and has no rate limiting as the existing checkLoginAttempts throttle only applies to the login flow. This enables automated enumeration of valid accounts for use in credential stuffing or targeted phishing. Only instances that have explicitly enabled the passwordReset option are affected, as it defaults to false. This issue has been fixed in version 4.29.0.