CVE-2026-48784
Symfony: UrlGenerator Dot-Segment Encoding Skips Every Other Chained `../` or `./` → Generated URL Collapses Off-Route Under RFC 3986 Normalization
No known exploitation. EPSS puts it in the 29th percentile. Fixed in 5.4.53.
No public exploit knownFix5.4.53Upgrade to this build
e.g. OID 1.3.6.1.4.1.25623.1.0.133417
What to do
Find your product and version, then upgrade to the build on the right.
- SymfonyAffected: < 5.4.53Upgrade to: not statedAffected: >= 6.0.0-BETA1, < 6.4.41Upgrade to: not statedAffected: >= 7.0.0-BETA1, < 7.4.13Upgrade to: not statedAffected: >= 8.0.0-BETA1, < 8.0.13Upgrade to: not statedStated by: CVE record
- Symfony RoutingAffected: < 5.4.53Upgrade to: not statedAffected: >= 6.0.0-BETA1, < 6.4.41Upgrade to: not statedAffected: >= 7.0.0-BETA1, < 7.4.13Upgrade to: not statedAffected: >= 8.0.0-BETA1, < 8.0.13Upgrade to: not statedStated by: CVE record
- Sensiolabs SymfonyAffected: < 5.4.53Upgrade to: 5.4.53Stated by: NVD
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.53, 6.4.41, 7.4.13, and 8.0.13, UrlGenerator::doGenerate() used strtr() dot-segment encoding that skipped every other chained ../ or ./ segment, allowing attacker-controlled route parameters to generate URLs that collapse to a different path under RFC 3986 normalization. This issue is fixed in versions 5.4.53, 6.4.41, 7.4.13, and 8.0.13.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 29th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
7 events over 20 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped, record updated
- OpenVAS check added
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Scored 6.1 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality LowSome restricted information is disclosed, but limited in scope
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1566Phishingmedium confidence
Sources
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