CVE-2026-40194

low

Published 2026-04-10 · Modified 2026-05-08

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CVSS v3

3.7

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS v4 NEW

—

not yet in upstream

VIR risk

3.7

Description

phpseclib has a variable-time HMAC comparison in SSH2::get_binary_packet() using != instead of hash_equals()

Predictions

Exploit likelihood

47%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

Debian Mixed 5 releases

Version	Status	Fixed in
trixie	Fixed	`2.0.48-3+deb13u2`
sid	Fixed	`2.0.53-1`
forky	Fixed	`2.0.53-1`
bullseye	Affected	—
bookworm	Fixed	`2.0.42-1+deb12u4`

Package impact

Ecosystem	Package	Vulnerable	Fixed
Packagist	phpseclib/phpseclib	`>=0.1.1,<1.0.28\|>=3.0.0,<3.0.51\|>=2.0.0,<2.0.53`
Packagist	phpseclib/phpseclib	`>=0.1.1,<1.0.28`	`1.0.28`
Packagist	phpseclib/phpseclib	`>=2.0.0,<2.0.53`	`2.0.53`
Packagist	phpseclib/phpseclib	`>=3.0.0,<3.0.51`	`3.0.51`
COMPOSER	phpseclib/phpseclib	`>= 0.1.1, < 1.0.28`	`1.0.28`
COMPOSER	phpseclib/phpseclib	`>= 3.0.0, < 3.0.51`	`3.0.51`
COMPOSER	phpseclib/phpseclib	`>= 2.0.0, < 2.0.53`	`2.0.53`

Application impact

Vendor	Product	Versions	Fixed
phpseclib	phpseclib	`{"endIncluding":"1.0.27"}`

References

CWEs

CWE-208

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.