CVE-2026-91777
📛 CVE Title
jackson-databind: quadratic forward-reference completion in Collection and Map deserializers
Description
Forward-reference completion for @JsonIdentityInfo object IDs in FasterXML jackson-databind performs a linear scan of the pending-reference accumulator for every resolved ID. The affected paths are CollectionDeserializer.CollectionReferringAccumulator.resolveForwardReference() and the equivalent implementation in MapDeserializer. When a document first creates N unresolved object-ID references in an identity-enabled collection or map and then defines those same IDs in reverse order, completion performs on the order of N * (N + 1) / 2 identity comparisons, so a shallow document whose size grows linearly causes quadratic CPU work during deserialization. The reporter instrumented equals() calls on the ID class and measured exactly 2,003,000 comparisons at N = 2,000, against zero comparisons in the pending-reference lookup path for an equally sized control in which every reference was already resolved. The input requires no deep nesting and no syntactically unusual JSON. Exploitation requires an application that deserializes attacker-influenced JSON into an identity-enabled collection or map. The fix replaces the repeated linear lookup with a keyed pending-reference structure.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- HeroDevs
- CVSS severity
- HIGH
- CVSS score
- 7.5 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Effective score
- 7.5 / 10 HIGH source: CNA overview
- CWE(s)
-
CWE-400 - Reserved
- 2026-09-15
- Published
- 2026-09-23 02:21 UTC
- Last updated
- 2026-09-23 14:05 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/91xxx/CVE-2026-91777.json
- Linked Threat
- CVE-2026-91777 — jackson-databind: quadratic forward-reference completion in Collection and Map deserializers
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-23 03:17:04 UTC
- NVD last modified
- 2026-09-23 15:17:25 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: 36c7be3b-2937-45df-85ea-ca7133ea542c
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0049 (probability of exploitation in next 30 days)
- EPSS percentile
- 41.11% vs all CVEs — higher = more likely to be exploited, as of 2026-09-23
NVD / KEV / EPSS data refreshed 2026-09-24 04:31 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-85003 - Assigner
- HeroDevs
- Published
- Sep 23, 2026, 2:21:48 AM
- Updated
- Sep 23, 2026, 2:05:17 PM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EUVD-reported EPSS
- 0.4900
- Vendors
- FasterXML
- Products
-
jackson-databind (3.2.0 ≤3.2.2)jackson-databind (2.5.0 ≤2.18.10)jackson-databind (2.19.0 ≤2.21.6)jackson-databind (3.0.0 ≤3.1.6)jackson-databind (2.22.0 ≤2.22.2)
ENISA description: Forward-reference completion for @JsonIdentityInfo object IDs in FasterXML jackson-databind performs a linear scan of the pending-reference accumulator for every resolved ID. The affected paths are CollectionDeserializer.CollectionReferringAccumulator.resolveForwardReference() and the equivalent implementation in MapDeserializer. When a document first creates N unresolved object-ID references in an identity-enabled collection or map and then defines those same IDs in reverse order, completion performs on the order of N * (N + 1) / 2 identity comparisons, so a shallow document whose size grows linearly causes quadratic CPU work during deserialization. The reporter instrumented equals() calls on the ID class and measured exactly 2,003,000 comparisons at N = 2,000, against zero comparisons in the pending-reference lookup path for an equally sized control in which every reference was already resolved. The input requires no deep nesting and no syntactically unusual JSON. Exploitation requires an application that deserializes attacker-influenced JSON into an identity-enabled collection or map. The fix replaces the repeated linear lookup with a keyed pending-reference structure.
Affected products (2)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| FasterXML | jackson-databind |
2.5.0 (affected),
2.19.0 (affected),
2.22.0 (affected)
|
— |
| FasterXML | jackson-databind |
3.0.0 (affected),
3.2.0 (affected)
|
— |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
- GHSA-cxp5-3px4-pw24 vendor-advisory
- FasterXML/jackson-databind#6204 patch
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (3)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/FasterXML/jackson-databind/issues/6204 36c7be3b-2937-45df-85ea-ca7133ea542c
- https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-cxp5-3px4-pw24 36c7be3b-2937-45df-85ea-ca7133ea542c
- https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-cxp5-3px4-pw24 134c704f-9b21-4f2e-91b3-4a467353bcc0
Remediations (10)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:fixitphill.com
Patch Microsoft Exchange CVE - 2026 -42897 with June 2026 security updates, keep EEMS mitigations during rollout, and verify OWA and mail flow.
2026-09-24 11:10 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-09-24 11:10 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-24 11:10 UTC -
web:support.microsoft.com
Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...
2026-09-24 11:10 UTC -
web:support.microsoft.com
This update for Windows 11, version 25H2 and 24H2 (KB5084597) incudes security improvements. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of Windows software updates. To view the ...
2026-09-24 11:10 UTC -
web:support.sap.com
SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.
2026-09-24 11:10 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-24 11:10 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-24 11:10 UTC -
web:www.wiz.io
Understand the critical aspects of CVE - 2026 -25177 with a detailed vulnerability assessment, exploitation potential, affected technologies, and remediation guidance.
2026-09-24 11:10 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's September 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-09-24 11:10 UTC
AI Forensic Analysis
Only Available for Registered Users. Sign in to view.
Raw JSON
The full cvelistV5 record. Download as CVE-2026-91777.json.
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