CASCACascade Atlas

Evidence dossier

CVE-2015-3246

libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a…

Exploited in the wild (CISA KEV since Aug 26, 2026). NVD reports CVSS 2.0 7.2. EPSS estimates 8.8% exploit likelihood as of Aug 27, 2026.

63.9–71.9Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.

State
PUBLISHED
Published
Aug 11, 2015
Updated
Aug 6, 2024
Evidence coverage
85%

Evidence chronology

What was known when

Download this view's receipt →
  1. Source dateSource date omittedFirst observed by CASCA
    CVE Program

    Record text: CVE Program Container

    Inspect raw assertion
    Field
    container
    Value
    CVE Program Container
    Original evidence ↗
  2. Source dateSource date omittedFirst observed by CASCA
    redhat

    Record text: libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.

    Inspect raw assertion
    Field
    container
    Value
    libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.
    Original evidence ↗
  3. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Red Hat Libuser Race Condition Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Red Hat Libuser Race Condition Vulnerability
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 8.8% probability · 94.79th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.087990000000; percentile 0.947880000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Aug 26, 2026 · first observed Aug 27, 2026

Exploit likelihood8.80%

FIRST EPSS · score date Aug 27, 2026 · 94.8th percentile · first observed Aug 27, 2026

SeverityCVSS 7.2

NVD · CVSS 2.0 · first observed Aug 26, 2026 · same-version scores align in this snapshot

Evidence detail

Source limits and decisions

Why each evidence state has this value

casca-unknown-reasons-v1
Exploitation statusEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
None
Affected productsSource-reported scope

The cited source assertion is retained while canonical product linkage remains open.

Revision
casca-factor-d-obligations-v1
Cutoff
Aug 27, 2026
Resolution
Resolve identity

Source comparison

Who said what

CVE ProgramDerivative copy
Record text

CVE Program Container

Inspect raw assertion
Field
container
Value
CVE Program Container
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
redhatOriginal assertion
Record text

libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.

Inspect raw assertion
Field
container
Value
libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Red Hat Libuser Race Condition Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Red Hat Libuser Race Condition Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

8.8% probability · 94.79th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.087990000000; percentile 0.947880000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
7Underlying assertions
1Canonical products
7Target assertions
0Constraint assertions

Grouped from 1 configuration nodes in this exact snapshot. Visual grouping is navigational; asset exposure and root cause require cited evidence.

Identity source boundaries
  • Cpe dictionary1,775,266 records · observed through 2026-07-21T06:45:29.809Z27d65b0f-b718-4b4f-bb79-c47c68d09dfa
  • Cpe match643,502 records · observed through 2026-07-21T08:13:17.697Z955dae73-7302-438b-aee1-058d7cc5d48e

2 scope groups

redhat · source assertedn/an/aDirect source scope
Affected: n/a
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "n/a"}]
NVD CPE · APPLICATIONredhatlibuserVulnerable target · 7 assertions
Any version (unconstrained) (<= 0.56.13-5); Version 0.60-1; Version 0.60-2; Version 0.60-3; Version 0.60-4; Version 0.60-5; Version 0.60-6Canonical identity product-b1ed0ed48f1fe200bea64eb49280a3c67d4e5b4b184c95b5af2fabdf9f04bae8Linked exact
Scope supported
Inspect raw assertions
  1. cpe:2.3:a:redhat:libuser:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    through including 0.56.13-5
    Match ID
    6de02055-abfb-4a4a-81df-c91e4371c5c4
  2. cpe:2.3:a:redhat:libuser:0.60-3:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 3
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    6e93b3b2-a2d2-4beb-bf4c-632a129b71cd
  3. cpe:2.3:a:redhat:libuser:0.60-6:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 6
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    7fe93709-708b-46a3-91a5-7aa9dc918cb9
  4. cpe:2.3:a:redhat:libuser:0.60-5:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 5
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    da7134c0-766f-47a8-acfa-d457b801c534
  5. cpe:2.3:a:redhat:libuser:0.60-2:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    e1c1a46c-08ec-4997-8bf2-ace6e313f644
  6. cpe:2.3:a:redhat:libuser:0.60-1:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    f65586f4-fa31-4f67-825e-1bdd1c904ae7
  7. cpe:2.3:a:redhat:libuser:0.60-4:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 4
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    0f3be074-6a6c-46a2-b9cc-39ba0efcc4eb

Affected-product evidence

Accepted scope and product mapping

0 canonical links · 2 source-reported links

Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Direct cve affected
Assertions
1
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
8a4e3c03-70a6-4220-b76f-2adaa15ec29c
Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Nvd cpe vulnerable target
Assertions
6
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
4f0064af-8484-4625-afb4-d3a1022ae7df5efc4460-ee74-4efd-bb3d-a7488a0e9d56928a89d2-517a-4e4e-96e1-31de6ae2e0feb9f4c24e-e674-4958-957c-00a43bc6ff3ad8fe7535-63c5-420d-bc0f-7d7b1b046d61da938387-da26-43fd-b695-67e0cbb48195

Assessments

CVSS by origin

7.2
NVDCVSS 2.0 · role Primary · priority eligiblevalid_matchAV:L/AC:L/Au:N/C:C/I:C/A:C
5.1
CVE Program sourceCVSS 3.1 · role Secondary · display onlyvalid_matchCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Evidence boundaries

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; remaining scope stays source-scoped.
  • NVD-carried upstream facts remain derivative; independent corroboration requires a separately authored source.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.
  • OSV aggregation and OSV-converted NVD material are not independent corroboration.
  • Red Hat facts are vendor assertions for the exact supplied products.
  • Nonmembership and not-yet-observed states are not proof of safety.