CVE-2026-78655
- Published25 Aug 2026
Description
Punk::Plugin::TOTP versions before 0.05 for Perl allow the second-factor attempt limit to be reset by replaying an earlier session cookie because the challenge route counts failures in the session. The POST handler on challenge_path keeps the failure count as tries inside the totp_pending record in the session, raising it on each rejected code and deleting the pending record once it reaches attempts, five by default. Punk::Session carries the session in a signed cookie unless the application declares a store, and keeps no server-side record, so an earlier value of the same session stays valid until the expiry stamped inside it. A client that saves the cookie before its failed attempts and presents it again gets the pending record back with its counter, and the limit never fires. The replayed record is accepted while its own expiry, pending_ttl seconds from the challenge and 300 by default, has not passed. Sessions declared with a store are not affected: the pending record and its counter then live server-side. The attempt limit does not bound guessing of the second factor, which is left to the per-address rate limit the plugin registers on the same path, 30 requests per 60 seconds.
CVSS 3.1 breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NRemediation
No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.
References
- https://metacpan.org/release/LNATION/Punk-0.32/view/lib/Punk/Session.pm
- https://metacpan.org/release/LNATION/Punk-TOTP-0.04/source/include/ptotp/ptotp_plugin.h
- https://metacpan.org/release/LNATION/Punk-TOTP-0.04/view/lib/Punk/Plugin/TOTP.pm
- https://metacpan.org/release/LNATION/Punk-TOTP-0.05/source/Changes
- http://www.openwall.com/lists/oss-security/2026/08/25/7
Related CVEs
Recent high-severity vulnerabilities sharing a weakness type.
Frequently asked
Is CVE-2026-78655 being actively exploited?
CVE-2026-78655 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.50%.
How severe is CVE-2026-78655?
CVE-2026-78655 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.50% probability of exploitation.
How do I fix CVE-2026-78655?
Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2026-78655 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.