Is there a public exploit for CVE-2026-9323?

No public exploit for CVE-2026-9323 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-9323?

CVE-2026-9323 scores CVSS 9.2 (v4.0), rated critical. EPSS puts the chance of exploitation in the next 30 days at 0.72%.

What does CVE-2026-9323 affect?

CVE-2026-9323 affects urwid urwid.

9.2 Critical

The urwid web display backend (urwid/display/web.py) generates web session identifiers (urwidid) in Screen.start() by concatenating two…

CVE-2026-9323

The urwid web display backend (urwid/display/web.py) generates web session identifiers (urwidid) in Screen.start() by concatenating two random.randrange(109) calls that use Python's Mersenne Twister PRNG, which is not cryptographically secure. Each call consumes approximately 30 bits of PRNG state, and the Mersenne Twister internal state is approximately 19,937 bits, so an attacker who observes approximately 334 session IDs (for example via the X-Urwid-ID HTTP response header) can fully reconstruct the internal state and predict all past and future session IDs (Path B). The same identifier is also used as the filename of a FIFO created in the world-listable /tmp directory (for example /tmp/urwid375487765176907690.in), so any local user on the host can list /tmp to enumerate active session tokens directly (Path A). With a valid session ID, an attacker can read the victim's terminal screen via the polling endpoint, inject keystrokes into the victim's session (yielding OS-level code execution with the session owner's privileges if the session runs a shell), and inject exit sequences or flood the FIFO to terminate or crash the session. A prior Bandit S311 warning on this usage was…

Assessment

CVSS: 9.2 (v4.0)
Severity: Critical
EPSS: 0.72% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 18 July 2026
Last updated: 8 November 2026
Affected: urwid · urwid
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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