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NVD / CVE Program· CNA mitre

CVE-2026-49017: In OpenStack Swift before 2.36.2 and 2.37.2, s3api middleware enters an infinite loop when processing a truncated aws-chunked PUT request bo

Noroxi assessment

Priority: Monitor (action score 28/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.35% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: OpenStack Swift 2.35.3, 2.36.2, 2.37.2.

Low priority for now. Upgrade to OpenStack Swift 2.35.3, 2.36.2, 2.37.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In OpenStack Swift before 2.36.2 and 2.37.2, s3api middleware enters an infinite loop when processing a truncated aws-chunked PUT request body. The StreamingInput class repeatedly appends an empty buffer and re-reads, causing the proxy-server worker handling the request to become permanently unresponsive with increasing CPU and memory consumption. An authenticated attacker can systematically exhaust all proxy-server workers, resulting in denial of service. The defect was introduced in Swift 2.36.0.

HighCVSS 7.1 · v4.0—No exploit Fix available
Published
May 26, 2026
Updated
Sep 24, 2026
EPSS
0.3% · 29th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · mitre
7.1
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-49017

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
openstackswift

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • openstack swift2.35.1 and later · before 2.35.3
  • openstack swift2.36.0 and later · before 2.36.2
  • openstack swift2.37.0 and later · before 2.37.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (mitre). Independent of NVD's CPE analysis and usually ahead of it.

  • OpenStack Swift

    • 2.36.0 and later · before 2.36.2affected · semver
    • 2.37.0 and later · before 2.37.2affected · semver
    • 2.35.1 and later · before 2.35.3affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:13swiftbefore 2.35.1-0+deb13u22.35.1-0+deb13u2
Debian:14swiftbefore 2.37.1-42.37.1-4
PyPIswiftfrom 2.36.0 · up to and including 2.36.1—
PyPIswiftfrom 2.37.0 · up to and including 2.37.1—

Same product

openstack: all records

Other highest-scoring records for the same primary product.

  • CVE-2012-4406OpenStack Object Storage (swift) before 1.7.0 uses the loads function in the pickle Python module unsafely when storing and loading metadata
    41Plan
  • CVE-2026-71190In OpenStack Swift through 2.38.0, the proxy server Accept header parser contains a regular expression vulnerable to catastrophic backtracki
    34Monitor
  • CVE-2016-0738OpenStack Object Storage (Swift) before 2.3.1 (Kilo), 2.4.x, and 2.5.x before 2.5.1 (Liberty) do not properly close server connections, whic
    31Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2017-8761Jun 2, 2021 · In OpenStack Swift through 2.10.1, 2.11.0 through 2.13.0, and 2.14.0, the proxy-server logs full tempurl paths, potentially leaking reusable
    17Monitor
  • ← EarlierCVE-2022-47950Jan 18, 2023 · An issue was discovered in OpenStack Swift before 2.28.1, 2.29.x before 2.29.2, and 2.30.0.
    26Monitor
  • Later →CVE-2026-50221Jun 23, 2026 · In OpenStack Swift before 2.37.2, proxy-server does not strip internal update headers (X-Container-Host, X-Container-Device, X-Delete-At-Hos
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
OpenStack Swift2.35.3Vendor (CNA)
OpenStack Swift2.36.2Vendor (CNA)
OpenStack Swift2.37.2Vendor (CNA)
debian:swift2.35.1-0+deb13u2 · Debian:13Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
X

Weakness class (CWE)

CWE-835 · Loop with Unreachable Exit Condition ('Infinite Loop')

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

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References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records