Security readout for executives and security teams
Plain-English summary
CVE-2026-42250 is a denial-of-service flaw in bzip2recover, a recovery utility included with bzip2. A specially crafted file can trigger memory corruption and crash the tool. Business impact is likely limited unless users or automated workflows process untrusted bzip2 files with bzip2recover.
Executive priority
Treat as a routine patching item unless bzip2recover is used in exposed or automated workflows. Prioritize systems that process external files, but this is not currently supported as an active-exploitation emergency by the provided sources.
Technical view
The issue is an off-by-one error causing an out-of-bounds write to a global buffer in bzip2recover. The CVE maps to CWE-787 and has CVSS 4.0 score 4.8. The source bundle states it is fixed by bzip2 commit 35d122a3df8b0cc4082a4d89fdc6ee99f375fe67.
Likely exposure
Exposure is most likely on systems where bzip2recover is installed and used against files from untrusted sources. The CVSS vector indicates local attack requirements and user interaction. Package-level affected version details are not provided in the sources.
Exploitation context
Sources describe a crafted-file crash and denial of service, not code execution. The source bundle says KEV is false, and no provided source reports active exploitation. Practical risk depends on whether bzip2recover is reachable in user workflows, support processes, or automated file recovery pipelines.
Researcher notes
The available data supports a local, user-assisted denial-of-service condition in bzip2recover. The patch reference is available, but package-specific affected and fixed versions are incomplete. Avoid assuming impact beyond crash/memory corruption without additional vendor analysis.
Mitigation direction
- Apply vendor or distribution updates that include commit 35d122a3df8b0cc4082a4d89fdc6ee99f375fe67.
- Avoid processing untrusted compressed files with bzip2recover until updated.
- Check OS vendor advisories for fixed package versions.
- Restrict use of bzip2recover in automated workflows handling external files.
Validation and detection
- Inventory systems with bzip2 and bzip2recover installed.
- Verify whether installed source or package includes the referenced fix commit.
- Review file-processing workflows for bzip2recover use on untrusted inputs.
- Monitor vendor and distribution advisories for package-specific remediation status.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-787: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-42250 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.8 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N——CERT-PLVulnerability scoring details
Base CVSS 4.0 score
4.8MediumVector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://cert.pl/en/posts/2026/05/CVE-2026-42250/CVE reference, CERT-PL · third-party-advisory
- https://sourceware.org/bzip2/CVE reference, CERT-PL · product
- https://inbox.sourceware.org/bzip2-devel/20260528145407.293768-1-mark@klomp.org/CVE reference, CERT-PL · vendor-advisory
- https://sourceware.org/cgit/bzip2/commit/?id=35d122a3df8b0cc4082a4d89fdc6ee99f375fe67CVE reference, CERT-PL · patch
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.