CVE-2026-5435 (GCVE-0-2026-5435)
Vulnerability from cvelistv5 – Published: 2026-04-28 11:58 – Updated: 2026-07-14 12:45
VLAI
EPSS
VEX
Title
Potential buffer overflow in ns_sprintrrf TSIG handling path
Summary
The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records.
Severity
7.3 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-28 15:15 UTC
CWE
- CWE-787 - Out-of-bounds write
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://sourceware.org/bugzilla/show_bug.cgi?id=34033 | issue-tracking |
| https://inbox.sourceware.org/libc-announce/7a655d… | mailing-list |
| https://cert-portal.siemens.com/productcert/html/… |
Impacted products
4 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| The GNU C Library | glibc |
Affected:
2.2 , ≤ *
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
guessed | |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
guessed |
Date Public
2026-04-02 02:11
{
"containers": {
"adp": [
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 7.3,
"baseSeverity": "HIGH",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2026-5435",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-04-28T15:15:07.411547Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-04-28T15:21:13.800Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
},
{
"affected": [
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-07-14T12:45:29.470Z",
"orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"shortName": "siemens-SADP"
},
"references": [
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
}
],
"x_adpType": "supplier"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "glibc",
"vendor": "The GNU C Library",
"versions": [
{
"lessThanOrEqual": "*",
"status": "affected",
"version": "2.2",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "shinobu"
}
],
"datePublic": "2026-04-02T02:11:00.000Z",
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records.\u003cbr\u003e"
}
],
"value": "The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records."
}
],
"impacts": [
{
"capecId": "CAPEC-100",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-100 Overflow Buffers"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-787",
"description": "CWE-787 Out-of-bounds write",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-04-28T11:58:54.962Z",
"orgId": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"shortName": "glibc"
},
"references": [
{
"tags": [
"issue-tracking"
],
"url": "https://sourceware.org/bugzilla/show_bug.cgi?id=34033"
},
{
"tags": [
"mailing-list"
],
"url": "https://inbox.sourceware.org/libc-announce/7a655d55-276f-41fe-b550-feb3ebb2ce91@redhat.com/T/#u"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "Potential buffer overflow in ns_sprintrrf TSIG handling path",
"x_generator": {
"engine": "Vulnogram 1.0.2"
}
}
},
"cveMetadata": {
"assignerOrgId": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"assignerShortName": "glibc",
"cveId": "CVE-2026-5435",
"datePublished": "2026-04-28T11:58:54.962Z",
"dateReserved": "2026-04-02T17:18:02.654Z",
"dateUpdated": "2026-07-14T12:45:29.470Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-5435",
"date": "2026-09-18",
"epss": "0.00237",
"percentile": "0.1506"
},
"microsoft_vex": {
"current_release_date": "2026-09-09T14:48:08.000Z",
"cve": "CVE-2026-5435",
"id": "msrc_CVE-2026-5435",
"initial_release_date": "2026-04-29T01:07:02.000Z",
"product_status:known_affected": "6",
"source": "Microsoft CSAF VEX",
"status": "final",
"title": "Potential buffer overflow in ns_sprintrrf TSIG handling path",
"url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-5435.json",
"version": "7"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "glibc",
"vendor": "The GNU C Library",
"versions": [
{
"lessThanOrEqual": "*",
"status": "affected",
"version": "2.2",
"versionType": "custom"
}
]
}
],
"source": "3ff69d7a-14f2-4f67-a097-88dee7810d18"
},
{
"affectedData": [
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
},
{
"defaultStatus": "unknown",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"vendor": "Siemens",
"versions": [
{
"lessThan": "V3.1.6",
"status": "affected",
"version": "V3.1.5",
"versionType": "custom"
}
]
}
],
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*",
"matchCriteriaId": "E6240DD2-E366-424F-BFA2-266E17793764",
"versionStartIncluding": "2.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records."
}
],
"id": "CVE-2026-5435",
"lastModified": "2026-07-14T13:19:01.360",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 7.3,
"baseSeverity": "HIGH",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 3.4,
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-5435",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-04-28T15:15:07.411547Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-04-28T13:19:22.290",
"references": [
{
"source": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"tags": [
"Third Party Advisory"
],
"url": "https://inbox.sourceware.org/libc-announce/7a655d55-276f-41fe-b550-feb3ebb2ce91@redhat.com/T/#u"
},
{
"source": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"tags": [
"Issue Tracking"
],
"url": "https://sourceware.org/bugzilla/show_bug.cgi?id=34033"
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
}
],
"sourceIdentifier": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-787"
}
],
"source": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-09-08T14:15:57+00:00",
"cve": "CVE-2026-5435",
"id": "CVE-2026-5435",
"initial_release_date": "2026-04-28T11:58:54.962000+00:00",
"product_status:fixed": "3078",
"product_status:known_affected": "23",
"product_status:known_not_affected": "6",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "glibc: glibc: Out-of-bounds write via TSIG record processing",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5435.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-09-11T01:44:47Z",
"cve": "CVE-2026-5435",
"id": "CVE-2026-5435",
"initial_release_date": "2026-04-30T02:30:45Z",
"product_status:first_fixed": "1",
"product_status:known_affected": "666",
"product_status:known_not_affected": "71",
"product_status:recommended": "895",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-5435",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-5435.json",
"version": "19"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 7.3,
"baseSeverity": "HIGH",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2026-5435",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-04-28T15:15:07.411547Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-04-28T15:21:08.263Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "glibc",
"vendor": "The GNU C Library",
"versions": [
{
"lessThanOrEqual": "*",
"status": "affected",
"version": "2.2",
"versionType": "custom"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "shinobu"
}
],
"datePublic": "2026-04-02T02:11:00.000Z",
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records.\u003cbr\u003e"
}
],
"value": "The deprecated functions ns_printrrf, ns_printrr and fp_nquery in the GNU C Library version 2.2 and newer fail to enforce the caller-supplied buffer length, and can result in an out-of-bounds write when printing TSIG records."
}
],
"impacts": [
{
"capecId": "CAPEC-100",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-100 Overflow Buffers"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-787",
"description": "CWE-787 Out-of-bounds write",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-04-28T11:58:54.962Z",
"orgId": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"shortName": "glibc"
},
"references": [
{
"tags": [
"issue-tracking"
],
"url": "https://sourceware.org/bugzilla/show_bug.cgi?id=34033"
},
{
"tags": [
"mailing-list"
],
"url": "https://inbox.sourceware.org/libc-announce/7a655d55-276f-41fe-b550-feb3ebb2ce91@redhat.com/T/#u"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "Potential buffer overflow in ns_sprintrrf TSIG handling path",
"x_generator": {
"engine": "Vulnogram 1.0.2"
}
}
},
"cveMetadata": {
"assignerOrgId": "3ff69d7a-14f2-4f67-a097-88dee7810d18",
"assignerShortName": "glibc",
"cveId": "CVE-2026-5435",
"datePublished": "2026-04-28T11:58:54.962Z",
"dateReserved": "2026-04-02T17:18:02.654Z",
"dateUpdated": "2026-04-28T15:21:13.800Z",
"state": "PUBLISHED"
},
"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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…