Security readout for executives and security teams
Plain-English summary
RPM could be tricked locally into applying file permissions or ownership to the wrong file through a symbolic link swap. A local unprivileged user could use this to gain higher privileges. This is mainly a risk on systems where RPM package operations occur while untrusted local users have access.
Executive priority
Address this as a high-priority local privilege escalation issue on shared or multi-user Linux systems. It is less urgent than a remote unauthenticated flaw, but compromise impact can be serious if an attacker already has local access.
Technical view
CVE-2021-35938 is a CWE-59 symbolic link handling flaw in RPM. During installation, RPM set permissions and credentials after creating a file. A local attacker could replace that file with a symlink to a security-critical file before those attributes were applied. The source bundle states the issue is fixed in RPM 4.18.0.
Likely exposure
Exposure is most likely on Linux systems using RPM versions before the vendor-fixed package or RPM 4.18.0. The attacker must already have local unprivileged access. Exact affected distribution versions are not fully enumerated in the provided sources.
Exploitation context
The provided sources describe local privilege escalation potential, but do not show active exploitation. The CVE is not listed as KEV in the source bundle. Treat exploit status as unconfirmed unless vendor advisories or threat intelligence say otherwise.
Researcher notes
Focus review on RPM package installation paths where file attributes are applied after file creation. The public bundle identifies the upstream fix, PR, and commit, but distribution backports may not report version 4.18.0 even when fixed.
Mitigation direction
- Upgrade RPM using the affected distribution's security update channel.
- Confirm the installed RPM package contains the CVE-2021-35938 fix or is RPM 4.18.0 or later.
- Prioritize multi-user systems and hosts where untrusted users can access local shells.
- Review Red Hat, SUSE, Gentoo, or relevant vendor guidance for backported fixes.
Validation and detection
- Inventory systems using RPM and record installed package versions.
- Compare installed vendor package builds against distribution advisories for CVE-2021-35938.
- Verify package updates completed successfully on representative hosts.
- Check whether untrusted local users have shell access on exposed systems.
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-59: 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-2021-35938 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://bugzilla.redhat.com/show_bug.cgi?id=1964114CVE reference
- https://bugzilla.suse.com/show_bug.cgi?id=1157880CVE reference
- https://access.redhat.com/security/cve/CVE-2021-35938CVE reference
- https://rpm.org/wiki/Releases/4.18.0CVE reference
- https://github.com/rpm-software-management/rpm/pull/1919CVE reference
- https://github.com/rpm-software-management/rpm/commit/25a435e90844ea98fe5eb7bef22c1aecf3a9c033CVE reference
- GLSA-202210-22CVE reference · vendor-advisory
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.
Improper Link Resolution Before File Access ('Link Following')
Improper Link Resolution Before File Access ('Link Following') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.