JavaScript engine only wrote partial return value to stack
Priority LOW 29CWE-457Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Partial Red Hat: 15 fixed, 3 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-457 and the CVSS impact.
Summary
On 64-bit platforms IonMonkey-JIT only wrote 32 bits of the 64-bit return value space on the stack. Baseline-JIT, however, read the entire 64 bits. This vulnerability was fixed in Firefox 141, Firefox ESR 115.26, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00432 37th percentileScored 2026-11-07
Fix Partial Firefox (Mozilla): 115.26, 128.13, 140.1 +1Thunderbird (Mozilla): 128.13, 140.1, 141Red Hat: 21 advisoriesRed Hat: 15 fixed, 3 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 |
|---|---|---|---|---|---|
| Mozilla | Firefox | — | 115.26, 128.13, 140.1, 141 | Patch available | CNA |
| Mozilla | Thunderbird | — | 128.13, 140.1, 141 | Patch available | CNA |
- Firefox VendorMozilla Affected — Fixed in 115.26, 128.13, 140.1, 141 Patch available CNA
- Thunderbird VendorMozilla Affected — Fixed in 128.13, 140.1, 141 Patch available CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* | before 115.26.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* | before 141.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* | 128.0 to before 128.13.0; 140.0 to before 140.1.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:* | before 128.13.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:* | before 141.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:* | 140.0 to before 140.1.0 | Vulnerable | Mozilla |
- cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions before 115.26.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* Versions before 141.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:* Versions 128.0 to before 128.13.0; 140.0 to before 140.1.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:* Versions before 128.13.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:* Versions before 141.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:* Versions 140.0 to before 140.1.0 Vulnerable ·Mozilla
Remediation
- Fix · CNA Firefox (Mozilla) Fixed in 115.26, 128.13, 140.1, 141
- Fix · CNA Thunderbird (Mozilla) Fixed in 128.13, 140.1, 141
Red Hat 21 advisories
- RHSA-2025:13676 Released 2025-08-12 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 8) thunderbird-128.13.0-3.el8_10
- RHSA-2025:13651 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) thunderbird-128.13.0-3.el8_6
- Red Hat Enterprise Linux AppStream E4S (v.8.6) thunderbird-128.13.0-3.el8_6
- Red Hat Enterprise Linux AppStream TUS (v.8.6) thunderbird-128.13.0-3.el8_6
- RHSA-2025:13649 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream EUS (v.9.4) thunderbird-128.13.0-3.el9_4
Show 18 more Red Hat advisories
- RHSA-2025:13650 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) thunderbird-128.13.0-3.el8_8
- Red Hat Enterprise Linux AppStream TUS (v.8.8) thunderbird-128.13.0-3.el8_8
- RHSA-2025:13648 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) thunderbird-128.13.0-3.el9_2
- RHSA-2025:13645 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v. 8.2) thunderbird-128.13.0-3.el8_2
- RHSA-2025:13647 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) thunderbird-128.13.0-3.el9_0
- RHSA-2025:13646 Released 2025-08-11 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) thunderbird-128.13.0-3.el8_4
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) thunderbird-128.13.0-3.el8_4
- RHSA-2025:12361 Released 2025-07-31 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v.8.6) firefox-128.13.0-1.el8_6
- Red Hat Enterprise Linux AppStream E4S (v.8.6) firefox-128.13.0-1.el8_6
- Red Hat Enterprise Linux AppStream TUS (v.8.6) firefox-128.13.0-1.el8_6
- RHSA-2025:12360 Released 2025-07-31 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.8.8) firefox-128.13.0-1.el8_8
- Red Hat Enterprise Linux AppStream TUS (v.8.8) firefox-128.13.0-1.el8_8
- RHSA-2025:12353 Released 2025-07-31 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v. 8.2) firefox-128.13.0-1.el8_2
- RHSA-2025:12302 Released 2025-07-30 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream AUS (v.8.4) firefox-128.13.0-1.el8_4
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) firefox-128.13.0-1.el8_4
- RHSA-2025:12278 Released 2025-07-30 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux Server (v. 7 ELS) firefox-128.13.0-1.el7_9
- RHSA-2025:12187 Released 2025-07-29 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 9) thunderbird-128.13.0-3.el9_6
- RHSA-2025:12188 Released 2025-07-29 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux AppStream (v. 10) thunderbird-128.13.0-3.el10_0
- RHSA-2025:12044 Released 2025-07-29 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream EUS (v.9.4) firefox-128.13.0-1.el9_4, firefox-x11-128.13.0-1.el9_4
- RHSA-2025:12046 Released 2025-07-29 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.9.0) firefox-128.13.0-1.el9_0
- RHSA-2025:12045 Released 2025-07-29 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) firefox-128.13.0-1.el9_2, firefox-x11-128.13.0-1.el9_2
- RHSA-2025:11797 Released 2025-07-28 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 10) firefox-128.13.0-1.el10_0
- RHSA-2025:11748 Released 2025-07-24 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 9) firefox-128.13.0-1.el9_6, firefox-x11-128.13.0-1.el9_6
- RHSA-2025:11747 Released 2025-07-24 · Red Hat rating Importantfirefox security update
- Red Hat Enterprise Linux AppStream (v. 8) firefox-128.13.0-1.el8_10
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2025:11797, RHSA-2025:12188 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2025:11747, RHSA-2025:13676 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2025:11748, RHSA-2025:12187 |
| Red Hat Enterprise Linux AppStream AUS (v. 8.2) | Fixed | RHSA-2025:12353, RHSA-2025:13645 |
| Red Hat Enterprise Linux AppStream AUS (v.8.4) | Fixed | RHSA-2025:12302, RHSA-2025:13646 |
| Red Hat Enterprise Linux AppStream AUS (v.8.6) | Fixed | RHSA-2025:12361, RHSA-2025:13651 |
| Red Hat Enterprise Linux AppStream E4S (v.8.6) | Fixed | RHSA-2025:12361, RHSA-2025:13651 |
| Red Hat Enterprise Linux AppStream E4S (v.8.8) | Fixed | RHSA-2025:12360, RHSA-2025:13650 |
| Red Hat Enterprise Linux AppStream E4S (v.9.0) | Fixed | RHSA-2025:12046, RHSA-2025:13647 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2025:12045, RHSA-2025:13648 |
| Red Hat Enterprise Linux AppStream EUS (v.9.4) | Fixed | RHSA-2025:12044, RHSA-2025:13649 |
| Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) | Fixed | RHSA-2025:12302, RHSA-2025:13646 |
| Red Hat Enterprise Linux AppStream TUS (v.8.6) | Fixed | RHSA-2025:12361, RHSA-2025:13651 |
| Red Hat Enterprise Linux AppStream TUS (v.8.8) | Fixed | RHSA-2025:12360, RHSA-2025:13650 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2025:12278 |
Timeline
- 2026-10-02 Threatist record created from CVE-2025-8027
- 2026-10-03 Alias added: GHSA-j3rx-39f7-r8hw
References
Advisory 7
- https://www.mozilla.org/security/advisories/mfsa2025-56/
- https://www.mozilla.org/security/advisories/mfsa2025-57/
- https://www.mozilla.org/security/advisories/mfsa2025-58/
- https://www.mozilla.org/security/advisories/mfsa2025-59/
- https://www.mozilla.org/security/advisories/mfsa2025-61/
- https://www.mozilla.org/security/advisories/mfsa2025-62/
- https://www.mozilla.org/security/advisories/mfsa2025-63/
More Mozilla Firefox vulnerabilities
- TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
- TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
- TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
- TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
- TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
- TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2025-8027 · CVE Program
- CVE-2025-8027 · NVD
- FIRST EPSS
- GHSA-j3rx-39f7-r8hw · GitHub Advisory Database · CC BY 4.0
- CVE-2025-8027 · Red Hat security data · CC BY 4.0
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