{"affected":[{"defaultStatus":"unaffected","ecosystem":"https://github.com/zephyrproject-rtos/zephyr","packageName":"zephyr","product":"zephyr","source":"CNA: zephyr","vendor":"zephyrproject","versions":[{"lessThan":"4.3.2","status":"affected","version":"1.13.0","versionType":"semver"},{"lessThan":"4.4.2","status":"affected","version":"4.4.0","versionType":"semver"}]}],"cveId":"CVE-2026-12519","cwes":["CWE-787"],"description":"The WNC-M14A2A LTE-M modem driver mishandles unsolicited %NOTIFYEV: events in on_cmd_socknotifyev() (drivers/modem/vendor_standalone/wncm14a2a.c). The response line is linearized into a fixed 40-byte stack buffer via net_buf_linearize(), which caps the copy at 39 bytes and returns out_len <= 39. The two quote-delimiter scanning loops, however, were bounded by len — the full CR/LF-delimited frame length returned by net_buf_findcrlf() — rather than by out_len.\n\nWhen a %NOTIFYEV: line longer than 39 bytes contains no \" within the linearized region, the loop indices p1/p2 walk past value[39] and read adjacent stack memory until a stray quote byte is found or the index reaches len. The over-read string is then passed to strncmp()/atoi()/LOG_*, and if a quote byte is found out of bounds the subsequent value[p2] = '\\0' performs a single-NUL out-of-bounds stack write at an attacker-influenced offset.\n\nThe %NOTIFYEV: payload carries network-derived content (LTIME network time, SIB1 base-station system information, CSPS/RRCSTATE), so a rogue cellular base station, a malicious or compromised modem module, or RF manipulation that induces an over-long notify line reaches the defect without any application interaction; the handler runs automatically on the unsolicited event in the modem RX thread.\n\nThe impact is out-of-bounds stack disclosure (into logs and parsing) and stack corruption that can crash the modem RX thread (denial of service). The write offset is only weakly controlled, so memory-safe code execution is not demonstrated. The fix bounds both scanning loops by out_len, keeping all accesses within the linearized buffer.","epss":{"date":"2026-11-03","percentile":0.14485,"score":0.00235},"exploits":[],"kev":null,"metrics":[{"score":5,"severity":"medium","source":"CNA: zephyr","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L","version":"3.1"},{"score":5,"severity":"medium","source":"NVD: vulnerabilities@zephyrproject.org","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L","version":"3.1"}],"modifiedAt":1793769519400,"publishedAt":1786983533758,"references":[{"source":"CNA: zephyr","tags":["patch"],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/c516cb7c14f8b0537811764daa94bedc50c230f3"},{"source":"CNA: zephyr","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8hrc-q8cp-6xhf"},{"source":"vulnerabilities@zephyrproject.org","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/c516cb7c14f8b0537811764daa94bedc50c230f3"},{"source":"vulnerabilities@zephyrproject.org","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8hrc-q8cp-6xhf"}],"remediation":[{"kind":"fix","source":"CNA: zephyr","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/zephyrproject-rtos/zephyr/commit/c516cb7c14f8b0537811764daa94bedc50c230f3"}],"revision":"fb1656b31adb887674ef1efc004ca24704ec40a5e2824560dc5e57d5c6dc9ea3","sources":[{"modifiedAt":1793768380703,"name":"CNA: zephyr","retrievedAt":1793769021198,"url":"https://www.cve.org/CVERecord?id=CVE-2026-12519"},{"modifiedAt":1793769519400,"name":"NVD","retrievedAt":1793772955735,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12519"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793769049510,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-12519"}],"ssvc":{"assessedAt":1786990895823,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Out-of-bounds stack read and write in Zephyr WNC-M14A2A modem socket-notify parsing","updatedAt":1793772955735}