Yelp: yelp-xsl: overly permissive content security policy in yelp allows host file disclosure from flatpak applications
Priority LOW 30CWE-693Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Partial Red Hat: 16 fixed, 1 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-693.
Summary
A flaw was found in Yelp due to an overly permissive Content Security Policy (CSP) implementation provided by yelp-xsl. A malicious Flatpak application can open crafted help content through the OpenURI portal. By embedding an untrusted CSS stylesheet within a structured SVG document, attacker-controlled content can bypass Flatpak's intended sandbox isolation, allowing Yelp to evaluate local XML inclusions and disclose arbitrary user-readable host files through remote CSS resource requests. This may result in the unauthorized disclosure of sensitive information.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00179 7th percentileScored 2026-11-07
Fix Partial Red Hat: 9 advisoriesRed Hat: 16 fixed, 1 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | — | 2:3.28.1-2.el7_9 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | 2:3.28.1-3.el8_10.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | — | 2:3.28.1-3.el8_4.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | — | 2:3.28.1-3.el8_4.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — | 2:3.28.1-3.el8_6.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | — | 2:3.28.1-3.el8_6.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — | 2:3.28.1-3.el8_8.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — | 2:3.28.1-3.el8_8.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | 2:40.3-3.el9_8.1 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — | 2:40.3-2.el9_2.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — | 2:40.3-2.el9_4.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — | 2:40.3-2.el9_6.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
- Red Hat Enterprise Linux 7 Extended Lifecycle Support VendorRed Hat Affected — Fixed in 2:3.28.1-2.el7_9 Patch available CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_10.2 Patch available CNA
- Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_4.2 Patch available CNA
- Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_4.2 Patch available CNA
- Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_6.2 Patch available CNA
- Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_6.2 Patch available CNA
- Red Hat Enterprise Linux 8.8 Telecommunications Update Service VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_8.2 Patch available CNA
- Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 2:3.28.1-3.el8_8.2 Patch available CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 2:40.3-3.el9_8.1 Patch available CNA
- Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 2:40.3-2.el9_2.2 Patch available CNA
- Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions VendorRed Hat Affected — Fixed in 2:40.3-2.el9_4.2 Patch available CNA
- Red Hat Enterprise Linux 9.6 Extended Update Support VendorRed Hat Affected — Fixed in 2:40.3-2.el9_6.2 Patch available CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* | 6.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Red Hat |
| cpe:2.3:a:gnome:yelp:*:*:*:*:*:*:*:* | before 49.1 | Vulnerable | GNOME |
- cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat
- cpe:2.3:a:gnome:yelp:*:*:*:*:*:*:*:* Versions before 49.1 Vulnerable ·GNOME
Remediation
Red Hat 9 advisories
- RHSA-2026:57417 Released 2026-08-20 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux Server (v. 7 ELS) yelp-2:3.28.1-2.el7_9, yelp-libs-2:3.28.1-2.el7_9, yelp-libs-2:3.28.1-2.el7_9.ppc
- Red Hat Enterprise Linux Server Optional (v. 7 ELS) yelp-devel-2:3.28.1-2.el7_9, yelp-devel-2:3.28.1-2.el7_9.ppc
- RHSA-2026:54666 Released 2026-08-13 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) yelp-2:3.28.1-3.el8_6.2, yelp-libs-2:3.28.1-3.el8_6.2
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) yelp-2:3.28.1-3.el8_6.2, yelp-libs-2:3.28.1-3.el8_6.2
- RHSA-2026:54637 Released 2026-08-13 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) yelp-2:40.3-2.el9_2.2, yelp-libs-2:40.3-2.el9_2.2
Show 6 more Red Hat advisories
- RHSA-2026:54624 Released 2026-08-13 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) yelp-2:3.28.1-3.el8_8.2, yelp-libs-2:3.28.1-3.el8_8.2
- Red Hat Enterprise Linux AppStream TUS (v.8.8) yelp-2:3.28.1-3.el8_8.2, yelp-libs-2:3.28.1-3.el8_8.2
- RHSA-2026:54605 Released 2026-08-13 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) yelp-2:3.28.1-3.el8_4.2, yelp-libs-2:3.28.1-3.el8_4.2
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) yelp-2:3.28.1-3.el8_4.2, yelp-libs-2:3.28.1-3.el8_4.2
- RHSA-2026:54539 Released 2026-08-13 · Red Hat rating Importantyelp security update
- Red Hat CodeReady Linux Builder EUS (v.9.6) yelp-devel-2:40.3-2.el9_6.2
- Red Hat Enterprise Linux AppStream EUS (v.9.6) yelp-2:40.3-2.el9_6.2, yelp-libs-2:40.3-2.el9_6.2
- RHSA-2026:54540 Released 2026-08-13 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) yelp-2:40.3-2.el9_4.2, yelp-libs-2:40.3-2.el9_4.2
- RHSA-2026:47178 Released 2026-08-03 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream (v. 9) yelp-2:40.3-3.el9_8.1, yelp-libs-2:40.3-3.el9_8.1
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) yelp-devel-2:40.3-3.el9_8.1
- RHSA-2026:47177 Released 2026-08-03 · Red Hat rating Importantyelp security update
- Red Hat Enterprise Linux AppStream (v. 8) yelp-2:3.28.1-3.el8_10.2, yelp-libs-2:3.28.1-3.el8_10.2
- Red Hat Enterprise Linux CRB (v. 8) yelp-devel-2:3.28.1-3.el8_10.2
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat CodeReady Linux Builder EUS (v.9.6) | Fixed | RHSA-2026:54539 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:47177 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:47178 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2026:54605 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2026:54666 |
| Red Hat Enterprise Linux AppStream E4S (v.8.8) | Fixed | RHSA-2026:54624 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:54637 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:54540 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:54539 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Fixed | RHSA-2026:54605 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) | Fixed | RHSA-2026:54666 |
| Red Hat Enterprise Linux AppStream TUS (v.8.8) | Fixed | RHSA-2026:54624 |
| Red Hat Enterprise Linux CRB (v. 8) | Fixed | RHSA-2026:47177 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2026:47178 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2026:57417 |
| Red Hat Enterprise Linux Server Optional (v. 7 ELS) | Fixed | RHSA-2026:57417 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-13601
- 2026-10-03 Alias added: GHSA-f4vh-qr53-q5gv
References
Advisory 14
- RHSA-2026:47177
- RHSA-2026:47178
- RHSA-2026:54539
- RHSA-2026:54540
- RHSA-2026:54605
- RHSA-2026:54624
- RHSA-2026:54637
- RHSA-2026:54666
- RHSA-2026:57417
- https://access.redhat.com/security/cve/CVE-2026-13601
- https://blogs.gnome.org/mcatanzaro/2026/05/11/flatpak-sandbox-escape-via-yelp/
- RHBZ#2494110
- https://gitlab.gnome.org/GNOME/yelp/-/work_items/238
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-13601.json
More Red Hat Enterprise Linux vulnerabilities
- TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
- TI-2018-10530 Code injection in [UNKNOWN] RichFaces KEVCVSS 3.1CRITICAL 9.8
- TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
- TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
- TI-2025-23530 Sudo before 1.9.17p1 allows local users to obtain root access because /etc/nsswitch.conf… KEVCVSS 3.1CRITICAL 9.3
- TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
Sources
- CVE-2026-13601 · CVE Program
- CVE-2026-13601 · NVD
- FIRST EPSS
- GHSA-f4vh-qr53-q5gv · GitHub Advisory Database · CC BY 4.0
- CVE-2026-13601 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences