CVE-2026-80603
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack_irc: fix parse_dcc() off-by-one OOB read
parse_dcc() treats data_end as an inclusive end pointer, but its only caller passes data_limit = ib_ptr + datalen, which points one past the last valid byte.
The newline search loop iterates while tmp <= data_end, so when no newline is present, *tmp is read at tmp == data_end, one byte beyond the region filled by skb_header_pointer().
irc_buffer is kmalloc'd as MAX_SEARCH_SIZE + 1 bytes and datalen is capped at MAX_SEARCH_SIZE, so the stray read does not fault.
Leer descripción completaMostrar menos
The byte is uninitialized or stale; if it contains an ASCII digit, simple_strtoul will consume it and produce a wrong DCC IP or port in the conntrack expectation. The extra allocation byte is also a fragile guard: if the cap or allocation size changes, this becomes a real out-of-bounds read.
Change the loop and its post-loop check to use strict less-than, consistent with the caller's exclusive-end convention. Update the function comment accordingly.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Puntuación base: 9.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.60%
- Percentil entre todas las CVEs puntuadas: 47
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto secundario
T1565.001Stored Data Manipulationimpact65 %
Vulnerabilidad remota de lectura fuera de límites en análisis de IRC que permite lectura de memoria no inicializada y corrupción de expectativas de conexión. AV:N, PR:N, UI:N confirma T1190. Impacto: acceso a datos en memoria (T1005) y manipulación de registros de conexión (T1565.001).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
- https://git.kernel.org/stable/c/2393f0bd7a467ad475598f3a5b9de27ca36e3037
- https://git.kernel.org/stable/c/2b70f61f569bb29acb380e6f616a1bbdee15668f
- https://git.kernel.org/stable/c/437e0a3854b3a44ec15afa9ab88ec215adf3a2fd
- https://git.kernel.org/stable/c/910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1
- https://git.kernel.org/stable/c/abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e
- https://git.kernel.org/stable/c/aff589556ed772cb1c0c2d7b4d91ec45c0c39416
- https://git.kernel.org/stable/c/eeef3b81f449560653662df2dde6f6fe247c5365
- https://git.kernel.org/stable/c/ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-80603",
"cveTags": [],
"metrics": {
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{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.1,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
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"exploitabilityScore": 3.9
}
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"published": "2026-08-28T08:16:44.187",
"references": [
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{
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}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_irc: fix parse_dcc() off-by-one OOB read\n\nparse_dcc() treats data_end as an inclusive end pointer, but its only\ncaller passes data_limit = ib_ptr + datalen, which points one past the\nlast valid byte.\n\nThe newline search loop iterates while tmp <= data_end, so when no\nnewline is present, *tmp is read at tmp == data_end, one byte beyond\nthe region filled by skb_header_pointer().\n\nirc_buffer is kmalloc'd as MAX_SEARCH_SIZE + 1 bytes and datalen is\ncapped at MAX_SEARCH_SIZE, so the stray read does not fault. The byte\nis uninitialized or stale; if it contains an ASCII digit, simple_strtoul\nwill consume it and produce a wrong DCC IP or port in the conntrack\nexpectation. The extra allocation byte is also a fragile guard: if the\ncap or allocation size changes, this becomes a real out-of-bounds read.\n\nChange the loop and its post-loop check to use strict less-than,\nconsistent with the caller's exclusive-end convention. Update the\nfunction comment accordingly."
}
],
"lastModified": "2026-08-29T07:16:45.330",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}