Red Hat Enterprise Linux 7 Extended Lifecycle…: Integer Overflow or Wraparound
CVE-2026-5121 is a high-severity integer overflow or wraparound vulnerability in Red Hat Enterprise Linux 7 Extended Lifecycle Support from Red Hat, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 1.09% chance of exploitation within 30 days, higher than 66% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update SIDIS Secured SmartPlug to V7.26.0310 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 15 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- 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
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by CNA (redhat.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | CNA (redhat.com) |
| CVSS 3.1 | 9.8 | Critical | CISA (ADP) |
Official description
A flaw was found in libarchive. On 32-bit systems, an integer overflow vulnerability exists in the zisofs block pointer allocation logic. A remote attacker can exploit this by providing a specially crafted ISO9660 image, which can lead to a heap buffer overflow. This could potentially allow for arbitrary code execution on the affected system.
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
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/advisories/GHSA-2vwv-vqpv-v8vcThird Party Advisory
Patches and release notes
- github.com/libarchive/libarchive/pull/2934Issue Tracking
Third-party and government advisories
- access.redhat.com/security/cve/CVE-2026-5121Third Party Advisory
Other references
- access.redhat.com/errata/RHSA-2026:10065
- access.redhat.com/errata/RHSA-2026:10097
- access.redhat.com/errata/RHSA-2026:11768
- access.redhat.com/errata/RHSA-2026:12071
- access.redhat.com/errata/RHSA-2026:12274
- access.redhat.com/errata/RHSA-2026:13812
- access.redhat.com/errata/RHSA-2026:14773
- access.redhat.com/errata/RHSA-2026:14937
- access.redhat.com/errata/RHSA-2026:15087
- access.redhat.com/errata/RHSA-2026:16008
- access.redhat.com/errata/RHSA-2026:16009
- access.redhat.com/errata/RHSA-2026:16030
- access.redhat.com/errata/RHSA-2026:16174
- access.redhat.com/errata/RHSA-2026:17596
- access.redhat.com/errata/RHSA-2026:19724
Other vulnerabilities in Red Hat Enterprise Linux 7 Extended Lifecycle Support
- 8.6 High severity
- 8.6 High severity
- 8.6 High severity
- 8.6 High severity
- 7.5 High severity
- 7.8 High severity
Recent Integer Overflow or Wraparound vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.8 High severity
- 7.5 High severity
- 8.6 High severity
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