CVE-2026-6042 (GCVE-0-2026-6042)

Vulnerability from cvelistv5 – Published: 2026-04-10 09:00 – Updated: 2026-04-10 15:54
VLAI
Title
musl libc GB18030 4-byte Decoder iconv.c iconv algorithmic complexity
Summary
A security flaw has been discovered in musl libc up to 1.2.6. Affected is the function iconv of the file src/locale/iconv.c of the component GB18030 4-byte Decoder. Performing a manipulation results in inefficient algorithmic complexity. The attack must be initiated from a local position. To fix this issue, it is recommended to deploy a patch.
Severity
4.8 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X
3.3 (Low)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C
3.3 (Low)
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:X/RL:O/RC:C
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-10 15:44 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-404 - Denial of Service
Assigner
VulDB CNA under the mitre root
CNA scorecard B 83/100 over 3752 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
musl libc Affected: 1.2.0
Affected: 1.2.1
Affected: 1.2.2
Affected: 1.2.3
Affected: 1.2.4
Affected: 1.2.5
Affected: 1.2.6
guessed Create a notification for this product.
Credits
0x001 (VulDB User) 0x001 (VulDB User)
Show details on NVD website
To clipboard 

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              "lang": "en",
              "time": "2026-04-09T02:00:00.000Z",
              "value": "VulDB entry created"
            },
            {
              "lang": "en",
              "time": "2026-04-09T19:58:49.000Z",
              "value": "VulDB entry last update"
            }
          ],
          "title": "musl libc GB18030 4-byte Decoder iconv.c iconv algorithmic complexity"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "1af790b2-7ee1-4545-860a-a788eba489b5",
        "assignerShortName": "VulDB",
        "cveId": "CVE-2026-6042",
        "datePublished": "2026-04-10T09:00:18.733Z",
        "dateReserved": "2026-04-09T17:34:11.256Z",
        "dateUpdated": "2026-04-10T15:54:06.200Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.