FKIE_CVE-2026-77420

Vulnerability from fkie_nvd - Published: 2026-09-23 19:19 - Updated: 2026-09-23 19:19
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
JLine is a Java library for handling console input. From 3.0.0 until 3.30.15 and 4.3.1, DefaultHistory.matchPatterns(String patterns, String line) in reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java converts the HISTORY_IGNORE configuration value into a Java regular expression while escaping only part of its syntax, allowing other regex metacharacters to reach the backtracking engine. An attacker who can control application or user configuration can supply a nested-quantifier expression that is reevaluated whenever a command is added to history, consuming excessive CPU and indefinitely blocking the reader thread. This issue is fixed in versions 3.30.15 and 4.3.1.
References
security-advisories@github.comhttps://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541
security-advisories@github.comhttps://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae
security-advisories@github.comhttps://github.com/jline/jline3/pull/2012
security-advisories@github.comhttps://github.com/jline/jline3/pull/2018
security-advisories@github.comhttps://github.com/jline/jline3/releases/tag/4.3.1
security-advisories@github.comhttps://github.com/jline/jline3/releases/tag/jline-3.30.15
security-advisories@github.comhttps://github.com/jline/jline3/security/advisories/GHSA-5q95-hrpc-m3w3
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "jline3",
          "vendor": "jline",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.0.0, \u003c 3.30.15"
            },
            {
              "status": "affected",
              "version": "\u003e= 4.0.0, \u003c 4.3.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "JLine is a Java library for handling console input. From 3.0.0 until 3.30.15 and 4.3.1, DefaultHistory.matchPatterns(String patterns, String line) in reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java converts the HISTORY_IGNORE configuration value into a Java regular expression while escaping only part of its syntax, allowing other regex metacharacters to reach the backtracking engine. An attacker who can control application or user configuration can supply a nested-quantifier expression that is reevaluated whenever a command is added to history, consuming excessive CPU and indefinitely blocking the reader thread. This issue is fixed in versions 3.30.15 and 4.3.1."
    }
  ],
  "id": "CVE-2026-77420",
  "lastModified": "2026-09-23T19:19:15.510",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-09-23T19:19:15.510",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/pull/2012"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/pull/2018"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/releases/tag/4.3.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/releases/tag/jline-3.30.15"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/jline/jline3/security/advisories/GHSA-5q95-hrpc-m3w3"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1333"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.



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.