Security readout for executives and security teams
Plain-English summary
Affected Spring WebFlux applications may accept XML input that bypasses the configured memory limit when Aalto processes it. A remote, unauthenticated request could therefore create serious resource or security impact. Exposure requires the specific WebFlux, XML, and Aalto combination; ordinary Spring applications are not automatically affected.
Executive priority
Treat as an urgent inventory and remediation issue because the published rating is critical and network exploitation requires no credentials. Focus first on public XML-processing services. Do not assume every Spring deployment is vulnerable; confirm WebFlux, Aalto, Jaxb2Decoder, XML exposure, and affected version conditions.
Technical view
Jaxb2Decoder does not correctly enforce maxInMemorySize when Spring WebFlux uses the Aalto XML processor. The issue is classified as CWE-770 and carries CVSS 3.1 score 9.8 with network access, low complexity, and no required privileges or user interaction. The supplied sources do not describe the precise failure mechanism or a fixed release.
Likely exposure
Prioritize internet-accessible Spring WebFlux endpoints that accept XML and use Aalto with Jaxb2Decoder. Listed affected branches span Spring Framework 7.0.0–7.0.8, 6.2.0–6.2.19, 6.1.0–6.1.28, 6.0.0–6.0.30, 5.3.0–5.3.49, and 5.2.25.RELEASE and earlier.
Exploitation context
The CVSS vector indicates remotely reachable, unauthenticated exploitation with low complexity and no user interaction. However, the source bundle does not report active exploitation, and the CVE is not listed as KEV. No exploit availability or observed attacks are established by the supplied evidence.
Researcher notes
The supplied record establishes a maxInMemorySize enforcement bypass and CWE-770 classification but provides no safe technical detail about trigger structure, demonstrated impact, patch commit, or fixed versions. The CVSS confidentiality and integrity ratings are high, yet the bundle does not explain those impacts. Avoid extrapolating beyond the vendor advisory and CVE record.
Mitigation direction
- Check Spring's advisory for confirmed fixed versions and upgrade instructions.
- Inventory WebFlux services using Aalto, Jaxb2Decoder, and XML request handling.
- Temporarily restrict untrusted access to affected XML endpoints where operationally feasible.
- Monitor application memory, request volume, restarts, and resource-exhaustion alerts.
Validation and detection
- Confirm deployed Spring Framework versions across production and build inventories.
- Verify whether Aalto is present directly or transitively in each service.
- Identify routes accepting XML through Spring WebFlux and Jaxb2Decoder.
- Review whether affected endpoints are internet-accessible or require authentication.
- After remediation, confirm deployed versions match current Spring vendor guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-770: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-47891 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://spring.io/security/cve-2026-47891CVE reference, vmware
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Allocation of Resources Without Limits or Throttling
Allocation of Resources Without Limits or Throttling represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.