CVE-2026-82402

Status: DeferredMedium (5.3)—
Severity5.3Medium · CVSS 4.0
Exploitation probability0.34 %higher than 26% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

Gogs is an open source self-hosted Git service. Prior to 0.15.0+dev, an unauthenticated attacker can provide a backslash-containing target to the /redirect endpoint, and similar post-action redirect flows are also affected. internal/urlx/urlx.go IsSameSite validates a normalized form of the target while cmd/gogs/internal/web/web.go getRedirect and other callers use the original value in the Location response. This backslash normalization mismatch lets browsers interpret the Location value as a scheme-relative external URL, allowing links on a trusted Gogs domain to redirect victims to attacker-controlled content for phishing. This vulnerability is fixed in 0.15.0+dev.

CVSS

Base score
5.3
Version
4.0
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.34 %
Percentile among all scored CVEs
26
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

ATT&CK mitigations that cover these techniques

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

CWEs

References

Show 5 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-82402",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-82402",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-20T01:58:24.208606Z"
        }
      }
    ],
    "cvssMetricV40": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "Safety": "NOT_DEFINED",
          "version": "4.0",
          "Recovery": "NOT_DEFINED",
          "baseScore": 5.3,
          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "exploitMaturity": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED",
          "userInteraction": "PASSIVE",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "subIntegrityImpact": "LOW",
          "vulnIntegrityImpact": "NONE",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "LOW",
          "vulnConfidentialityImpact": "NONE",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
        }
      }
    ]
  },
  "affected": [
    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "gogs",
          "product": "gogs",
          "versions": [
            {
              "status": "affected",
              "version": "< 0.15.0+dev"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-10-14T19:17:21.660",
  "references": [
    {
      "url": "https://github.com/gogs/gogs/blob/main/CHANGELOG.md#0150dev-main",
      "source": "security-advisories@github.com"
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    {
      "url": "https://github.com/gogs/gogs/commit/0aa820e6d572771551871c0b5f5f32dffc565e3e",
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/gogs/gogs/pull/8391",
      "source": "security-advisories@github.com"
    },
    {
      "url": "https://github.com/gogs/gogs/security/advisories/GHSA-3g28-2vwg-gxq6",
      "source": "security-advisories@github.com"
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ],
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-601"
        }
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    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Gogs is an open source self-hosted Git service. Prior to 0.15.0+dev, an unauthenticated attacker can provide a backslash-containing target to the /redirect endpoint, and similar post-action redirect flows are also affected. internal/urlx/urlx.go IsSameSite validates a normalized form of the target while cmd/gogs/internal/web/web.go getRedirect and other callers use the original value in the Location response. This backslash normalization mismatch lets browsers interpret the Location value as a scheme-relative external URL, allowing links on a trusted Gogs domain to redirect victims to attacker-controlled content for phishing. This vulnerability is fixed in 0.15.0+dev."
    }
  ],
  "lastModified": "2026-10-20T02:17:12.277",
  "sourceIdentifier": "security-advisories@github.com"
}