CVE-2026-34209: wevm mppx · Authentication Bypass by Capture-replay
Affects wevm mppxSource CVE Database V5
Not known to be exploited · CVSS 7.5 High : upgrade to 0.4.11 soon.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.4.11
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 31 Mar 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 wevm mppx to 0.4.11.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| wevmmppx | Affected
| Fixed in
|
AI-suggested
Upgrade to version 0.4.11 or later of the wevm mppx interface, where the validation logic has been corrected to use a less-than-or-equal-to comparison. This patch effectively prevents the described authentication bypass and channel griefing. No additional mitigation is required once the update is applied.
Description
mppx is a TypeScript interface for machine payments protocol. Prior to version 0.4.11, the tempo/session cooperative close handler validated the close voucher amount using "<" instead of "<=" against the on-chain settled amount. An attacker could submit a close voucher exactly equal to the settled amount, which would be accepted without committing any new funds, effectively closing or griefing the channel for free. This issue has been patched in version 0.4.11.