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Fencer Vulns
high 7.5

CVE-2026-91777 json

jackson-databind: quadratic forward-reference completion in Collection and Map deserializers

published 2026-09-23 47 d ago modified 2026-09-30 40 d ago also EUVD-2026-85003 , GHSA-cxp5-3px4-pw24

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits
0
none known

Summary

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.

Patch / fix

  • maven com.fasterxml.jackson.core:jackson-databind 2.18.11, 2.21.7, 2.22.3
  • maven tools.jackson.core:jackson-databind 3.1.7, 3.2.3
  • com.fasterxml.jackson.core jackson-databind 2.18.11, 2.21.7, 2.22.3
  • tools.jackson.core jackson-databind 3.1.7, 3.2.3
  • jackson-databind Debian 14 2.18.11-1

debian advisories DEBIAN-CVE-2026-91777

  • jackson-databind RHEL 9 2.21.6-1.el9_8.1
  • pki-jackson-databind RHEL 9 2.21.6-1.el9_8.1

red hat advisories RHSA-2026:85231

  • jackson-databind SLES for SAP applications 16.0, SLES 16.0 2.18.11-160000.1.1
  • jackson-core SLES for SAP applications 16.0, SLES 16.0 2.18.11-160000.1.1
  • jackson-annotations SLES for SAP applications 16.0, SLES 16.0 2.18.11-160000.1.1
  • jackson-core SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.18.11-150200.3.30.1
  • jackson-databind SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.18.11-150200.3.36.1
  • jackson-annotations SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.18.11-150200.3.28.1
  • jackson-dataformat-xml SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.18.11-150200.5.8.1
  • jackson-dataformats-binary SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.18.11-150200.3.29.1

suse advisories SUSE-SU-2026:24149-1SUSE-SU-2026:4394-1

  • jackson-databind openSUSE Leap 16.0 2.18.11-160000.1.1
  • jackson-core openSUSE Leap 16.0 2.18.11-160000.1.1
  • jackson-annotations openSUSE Leap 16.0 2.18.11-160000.1.1
  • jackson-databind openSUSE Tumbleweed 2.18.11-1.1

opensuse advisories openSUSE-SU-2026:22034-1openSUSE-SU-2026:11877-1

  • xsom AlmaLinux 8 0-19.20110809svn.module_el8.5.0+2577+9e95fe00
  • slf4j AlmaLinux 8 1.7.25-4.module_el8.5.0+2577+9e95fe00
  • stax-ex AlmaLinux 8 1.7.7-8.module_el8.5.0+2577+9e95fe00
  • velocity AlmaLinux 8 1.7-24.module_el8.5.0+2577+9e95fe00
  • xalan-j2 AlmaLinux 8 2.7.1-38.module_el8.5.0+2577+9e95fe00
  • javassist AlmaLinux 8 3.18.1-8.module_el8.5.0+2577+9e95fe00
  • xerces-j2 AlmaLinux 8 2.11.0-34.module_el8.5.0+2577+9e95fe00
  • slf4j-jdk14 AlmaLinux 8 1.7.25-4.module_el8.5.0+2577+9e95fe00

almalinux advisories ALSA-2026:90909ALSA-2026:85231

  • xsom Rocky Linux 8 0-19.20110809svn.module+el8.10.0+1763+c7c02164
  • xsom Rocky Linux 8 0-19.20110809svn.module+el8.10.0+2052+1b0fb438
  • slf4j Rocky Linux 8 1.7.25-4.module+el8.10.0+1763+c7c02164
  • slf4j Rocky Linux 8 1.7.25-4.module+el8.10.0+2052+1b0fb438
  • slf4j Rocky Linux 8 1.7.25-4.module+el8.6.0+843+5a13dac3
  • slf4j Rocky Linux 8 1.7.25-4.module+el8.3.0+74+855e3f5d
  • slf4j Rocky Linux 8 1.7.25-4.module+el8.10.0+2003+8aeac9cb
  • stax-ex Rocky Linux 8 1.7.7-8.module+el8.10.0+1763+c7c02164

rocky linux advisories RLSA-2026:90909RLSA-2026:85231

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-91777 updated cvss 7.5

com.fasterxml.jackson.core/jackson-databind: tools.jackson.core:jackson-databind: Jackson-databind: Denial of Service via quadratic forward-reference completion

  • Red Hat OpenShift Developer Tools and Services jenkins, jenkins-2-plugins Red Hat build of Apache Camel - HawtIO 4 jackson-databind Red Hat build of Apache Camel 4 for Quarkus 3 jackson-databind Red Hat build of Apache Camel for Spring Boot 4 jackson-databind Red Hat build of Apicurio Registry 3 jackson-databind Red Hat build of Debezium 3 jackson-databind
    +2 more products
    Red Hat Data Grid 8 jackson-databind Red Hat Enterprise Linux 10 dogtag-pki
    affected: workaround, no fix available
  • Red Hat JBoss Enterprise Application Platform 7 jackson-databind
    affected: workaround, no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform 8 jackson-databind Red Hat OpenShift AI (RHOAI) rhoai/odh-modelmesh-rhel9, rhoai/odh-spark-operator-rhel9
    affected: workaround, no fix available
  • Red Hat Single Sign-On 7 jackson-databind
    affected: workaround, no fix planned “Will not fix”
  • Red Hat OpenShift Developer Tools and Services 4.12 ocp-tools-4/jenkins-rhel8 1792044326
    fixed: vendor fix RHSA-2026:88152
  • Red Hat OpenShift Developer Tools and Services 4.13 ocp-tools-4/jenkins-rhel8 1792044327
    fixed: vendor fix RHSA-2026:88149
  • Red Hat OpenShift Developer Tools and Services 4.14 ocp-tools-4/jenkins-rhel8 1792044382
    fixed: vendor fix RHSA-2026:88151
  • Red Hat OpenShift Developer Tools and Services 4.15 ocp-tools-4/jenkins-rhel8 1792044386
    fixed: vendor fix RHSA-2026:88150
show 19 more
  • Red Hat OpenShift Developer Tools and Services 4.16 ocp-tools-4/jenkins-rhel9 1792040287
    fixed: vendor fix RHSA-2026:88156
  • Red Hat OpenShift Developer Tools and Services 4.17 ocp-tools-4/jenkins-rhel9 1792040131
    fixed: vendor fix RHSA-2026:88159
  • Red Hat OpenShift Developer Tools and Services 4.18 ocp-tools-4/jenkins-rhel9 1792041514
    fixed: vendor fix RHSA-2026:88153
  • Red Hat OpenShift Developer Tools and Services 4.19 ocp-tools-4/jenkins-rhel9 1792040733
    fixed: vendor fix RHSA-2026:88158
  • Red Hat OpenShift Developer Tools and Services 4.20 ocp-tools-4/jenkins-rhel9 1792040081
    fixed: vendor fix RHSA-2026:88157
  • Red Hat OpenShift Developer Tools and Services 4.21 ocp-tools-4/jenkins-rhel9 1792040096
    fixed: vendor fix RHSA-2026:88155
  • Red Hat OpenShift Developer Tools and Services 4.22 ocp-tools-4/jenkins-rhel9 1792040428
    fixed: vendor fix RHSA-2026:88154
  • Red Hat Build of Apache Camel 3.33.4.redhat jackson-databind 2.21.7.redhat-00001
    fixed: vendor fix RHSA-2026:83670
  • Red Hat build of Keycloak 26.6 rhbk/keycloak-rhel9 26.6-24, rhbk/keycloak-rhel9-operator 26.6-24, rhbk/keycloak-operator-bundle 26.6.8-2
    fixed: vendor fix RHSA-2026:95762
  • Red Hat build of Keycloak 26.6.8
    fixed: vendor fix RHSA-2026:95761
  • Red Hat build of Quarkus 3.27.6.redhat jackson-databind 2.21.7.redhat-00001
    fixed: vendor fix RHSA-2026:83082
  • Red Hat build of Quarkus 3.33.4.redhat jackson-databind 2.21.7.redhat-00001
    fixed: vendor fix RHSA-2026:83520
  • Red Hat Enterprise Linux AppStream (v. 8) slf4j 1.7.25-4.module+el8.10.0+20993+d0f024b0, stax-ex 1.7.7-8.module+el8.10.0+20993+d0f024b0, velocity 1.7-24.module+el8.10.0+20993+d0f024b0, bea-stax 1.2.0-16.module+el8.10.0+20993+d0f024b0, xalan-j2 2.7.1-38.module+el8.10.0+20993+d0f024b0, javassist 3.18.1-8.module+el8.10.0+20993+d0f024b0, +27 more
    fixed: vendor fix RHSA-2026:90909
  • Red Hat Enterprise Linux AppStream (v. 9) jackson-databind 2.21.6-1.el9_8.1, pki-jackson-databind 2.21.6-1.el9_8.1
    fixed: vendor fix RHSA-2026:85231
  • Red Hat Enterprise Linux AppStream E4S (v.9.2) jackson-databind 2.21.6-1.el9_2.1, pki-jackson-databind 2.21.6-1.el9_2.1
    fixed: vendor fix RHSA-2026:89924
  • Red Hat Enterprise Linux AppStream E4S (v.9.4) jackson-core 2.21.6-1.el9_4, pki-jackson-core 2.21.6-1.el9_4, jackson-databind 2.21.6-1.el9_4.1, jackson-annotations 2.21-1.el9_4.1, jackson-modules-base 2.21.6-1.el9_4, pki-jackson-databind 2.21.6-1.el9_4.1, +5 more
    fixed: vendor fix RHSA-2026:93444
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) jackson-core 2.21.6-1.el9_6, pki-jackson-core 2.21.6-1.el9_6, jackson-databind 2.21.6-1.el9_6.1, jackson-modules-base 2.21.6-1.el9_6, pki-jackson-databind 2.21.6-1.el9_6.1, jackson-jaxrs-providers 2.21.6-1.el9_6, +3 more
    fixed: vendor fix RHSA-2026:89734
  • Red Hat OpenShift AI 2.25 rhoai/odh-trustyai-service-rhel9 1790933094
    fixed: vendor fix RHSA-2026:87410
  • Red Hat Exploit Intelligence exploit-intelligence/agent-client-rhel9 Red Hat OpenShift Developer Tools and Services 4.12 ocp-tools-4/jenkins-agent-base-rhel8 1792044376 Red Hat OpenShift Developer Tools and Services 4.13 ocp-tools-4/jenkins-agent-base-rhel8 1792044361 Red Hat OpenShift Developer Tools and Services 4.14 ocp-tools-4/jenkins-agent-base-rhel8 1792044402 Red Hat OpenShift Developer Tools and Services 4.15 ocp-tools-4/jenkins-agent-base-rhel8 1792044379 Red Hat OpenShift Developer Tools and Services 4.16 ocp-tools-4/jenkins-agent-base-rhel9 1792040156
    not affected: vulnerable code not present

33 more not affected in the full advisory

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
47 d ago

Exploit prediction

0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-cxp5-3px4-pw24 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
maven com.fasterxml.jackson.core:jackson-databind
>=2.19.0, <2.21.7
>=2.5.0, <2.18.11
>=2.22.0, <2.22.3
2.21.7
2.18.11
2.22.3
maven tools.jackson.core:jackson-databind
>=3.0.0, <3.1.7
>=3.2.0, <3.2.3
3.1.7
3.2.3

Affected products

  • FasterXML jackson-databind

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.