CVE-2026-12519 (GCVE-0-2026-12519)
Vulnerability from cvelistv5 – Published: 2026-08-17 16:18 – Updated: 2026-08-17 18:22
VLAI
EPSS
VEX
Title
Out-of-bounds stack read and write in Zephyr WNC-M14A2A modem socket-notify parsing
Summary
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.
When 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.
The %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.
The 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.
Severity
5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-17 18:21 UTC
CWE
- CWE-787 - memory-safety
Assigner
References
2 references
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| zephyrproject | zephyr |
Affected:
1.13.0 , < 4.4.2
(semver)
|
guessed |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-12519",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-08-17T18:21:35.823541Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T18:22:49.443Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
"defaultStatus": "unaffected",
"packageName": "zephyr",
"product": "zephyr",
"programFiles": [
"drivers/modem/vendor_standalone/wncm14a2a.c"
],
"vendor": "zephyrproject",
"versions": [
{
"lessThan": "4.4.2",
"status": "affected",
"version": "1.13.0",
"versionType": "semver"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "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 \u003c= 39. The two quote-delimiter scanning loops, however, were bounded by len \u2014 the full CR/LF-delimited frame length returned by net_buf_findcrlf() \u2014 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] = \u0027\\0\u0027 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."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 5,
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-787",
"description": "memory-safety",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T16:18:53.758Z",
"orgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
"shortName": "zephyr"
},
"references": [
{
"name": "Fix commit",
"tags": [
"patch"
],
"url": "https://github.com/zephyrproject-rtos/zephyr/commit/c516cb7c14f8b0537811764daa94bedc50c230f3"
},
{
"name": "GHSA-8hrc-q8cp-6xhf",
"url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8hrc-q8cp-6xhf"
}
],
"title": "Out-of-bounds stack read and write in Zephyr WNC-M14A2A modem socket-notify parsing",
"x_generator": {
"engine": "cvelib 1.8.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
"assignerShortName": "zephyr",
"cveId": "CVE-2026-12519",
"datePublished": "2026-08-17T16:18:53.758Z",
"dateReserved": "2026-06-17T12:59:10.511Z",
"dateUpdated": "2026-08-17T18:22:49.443Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-12519",
"date": "2026-08-19",
"epss": "0.00163",
"percentile": "0.06012"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-12519\",\"sourceIdentifier\":\"vulnerabilities@zephyrproject.org\",\"published\":\"2026-08-17T17:16:38.867\",\"lastModified\":\"2026-08-17T19:16:24.140\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"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 \u003c= 39. The two quote-delimiter scanning loops, however, were bounded by len \u2014 the full CR/LF-delimited frame length returned by net_buf_findcrlf() \u2014 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] = \u0027\\\\0\u0027 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.\"}],\"affected\":[{\"source\":\"vulnerabilities@zephyrproject.org\",\"affectedData\":[{\"vendor\":\"zephyrproject\",\"product\":\"zephyr\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com/zephyrproject-rtos/zephyr\",\"packageName\":\"zephyr\",\"programFiles\":[\"drivers/modem/vendor_standalone/wncm14a2a.c\"],\"versions\":[{\"version\":\"1.13.0\",\"lessThan\":\"4.4.2\",\"versionType\":\"semver\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"vulnerabilities@zephyrproject.org\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L\",\"baseScore\":5.0,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"ADJACENT_NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"LOW\",\"availabilityImpact\":\"LOW\"},\"exploitabilityScore\":1.6,\"impactScore\":3.4}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-17T18:21:35.823541Z\",\"id\":\"CVE-2026-12519\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"vulnerabilities@zephyrproject.org\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-787\"}]}],\"references\":[{\"url\":\"https://github.com/zephyrproject-rtos/zephyr/commit/c516cb7c14f8b0537811764daa94bedc50c230f3\",\"source\":\"vulnerabilities@zephyrproject.org\"},{\"url\":\"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8hrc-q8cp-6xhf\",\"source\":\"vulnerabilities@zephyrproject.org\"}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-12519\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-17T18:21:35.823541Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-17T18:21:57.219Z\"}}], \"cna\": {\"title\": \"Out-of-bounds stack read and write in Zephyr WNC-M14A2A modem socket-notify parsing\", \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 5, \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L\"}}], \"affected\": [{\"vendor\": \"zephyrproject\", \"product\": \"zephyr\", \"versions\": [{\"status\": \"affected\", \"version\": \"1.13.0\", \"lessThan\": \"4.4.2\", \"versionType\": \"semver\"}], \"packageName\": \"zephyr\", \"programFiles\": [\"drivers/modem/vendor_standalone/wncm14a2a.c\"], \"collectionURL\": \"https://github.com/zephyrproject-rtos/zephyr\", \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://github.com/zephyrproject-rtos/zephyr/commit/c516cb7c14f8b0537811764daa94bedc50c230f3\", \"name\": \"Fix commit\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8hrc-q8cp-6xhf\", \"name\": \"GHSA-8hrc-q8cp-6xhf\"}], \"x_generator\": {\"engine\": \"cvelib 1.8.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"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 \u003c= 39. The two quote-delimiter scanning loops, however, were bounded by len \\u2014 the full CR/LF-delimited frame length returned by net_buf_findcrlf() \\u2014 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] = \u0027\\\\0\u0027 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.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-787\", \"description\": \"memory-safety\"}]}], \"providerMetadata\": {\"orgId\": \"e2e69745-5e70-4e92-8431-deb5529a81ad\", \"shortName\": \"zephyr\", \"dateUpdated\": \"2026-08-17T16:18:53.758Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-12519\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-17T18:22:49.443Z\", \"dateReserved\": \"2026-06-17T12:59:10.511Z\", \"assignerOrgId\": \"e2e69745-5e70-4e92-8431-deb5529a81ad\", \"datePublished\": \"2026-08-17T16:18:53.758Z\", \"assignerShortName\": \"zephyr\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Loading…
Loading…