CyberSecBulletin
CVE-2026-64313NVD status: Modified

Linux: Integer Overflow or Wraparound

Published Updated By the CyberSecBulletin desk

CVE-2026-64313 is a high-severity integer overflow or wraparound vulnerability in Linux, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions d11b2bb99bec1f5557c01cac42231e23745f49b8, b709e0e768766abe29a49e1c1922a1604be602f4, 24a54dfa06d09813b4802a374fad3d2c0e16a884 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to d11b2bb99bec1f5557c01cac42231e23745f49b8 or b709e0e768766abe29a49e1c1922a1604be602f4 or 24a54dfa06d09813b4802a374fad3d2c0e16a884 or 677450e5ef850c4d28b7956aa01104548c2a894e, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.261 or 5.15.212 or 6.1.178 or 6.6.145, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, d11b2bb99bec1f5557c01cac42231e23745f49b8; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, b709e0e768766abe29a49e1c1922a1604be602f4; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, 24a54dfa06d09813b4802a374fad3d2c0e16a884; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, 677450e5ef850c4d28b7956aa01104548c2a894e; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, 5275e0fca256d081e2e7d4ba3dd8216c6e50d44e; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, 774ddddf5eb26eeca177350413e3e2bc50930ee9; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, ebaae7c4251cc0cdb2602f334d4f08a3e82d271e; 3c4b23901a0c766879dff680cd6bdab47bcdbbd2 up to, but not including, 27b536a2ec8e2f85a0380c2d13c9ecbc7aaab406; and 1 more rangesd11b2bb99bec1f5557c01cac42231e23745f49b8, b709e0e768766abe29a49e1c1922a1604be602f4, 24a54dfa06d09813b4802a374fad3d2c0e16a884, 677450e5ef850c4d28b7956aa01104548c2a894e, 5275e0fca256d081e2e7d4ba3dd8216c6e50d44e, 774ddddf5eb26eeca177350413e3e2bc50930ee9
LinuxLinux Kernel4.8 up to, but not including, 5.10.261; 5.11 up to, but not including, 5.15.212; 5.16 up to, but not including, 6.1.178; 6.2 up to, but not including, 6.6.145; 6.7 up to, but not including, 6.12.96; 6.13 up to, but not including, 6.18.39; 6.19 up to, but not including, 7.1.45.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: crypto: ecc - Fix carry overflow in vli multiplication The carry flag calculation fails when r01.m_high is saturated (0xFFFFFFFFFFFFFFFF) and addition of lower bits overflows. The condition (r01.m_high < product.m_high) doesn't handle the case where r01.m_high == product.m_high and an additional carry exists from lower-bit overflow. When commit 3c4b23901a0c ("crypto: ecdh - Add ECDH software support") introduced crypto/ecc.c, it split the muladd() function in the micro-ecc library into separate mul_64_64() and add_128_128() helpers. It seems the check got lost in translation. Add proper handling for this boundary by accounting for the carry from the lower addition.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Integer Overflow or Wraparound

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

How developers prevent this class of flaw

  • Ensure that all protocols are strictly defined, such that all out-of-bounds behavior can be identified simply, and require strict conformance to the protocol.
  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. If possible, choose a language or compiler that performs automatic bounds checking.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Use libraries or frameworks that make it easier to handle numbers without unexpected consequences. Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++).

More Integer Overflow or Wraparound vulnerabilities (CWE-190)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Integer Overflow or Wraparound vulnerabilities

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