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NVD / CVE Program· CNA VulnCheck

CVE-2026-93838: SGLang through 0.5.20 Unbounded Memory Allocation via STAGING_REQ chunk_idx

Noroxi assessment

Priority: Monitor (action score 32/100)

  • 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: 0.65% (FIRST EPSS); higher than 51.5% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: python-sglang (openSUSE:Tumbleweed) 0.5.20-1.1.

Low priority for now. Upgrade to python-sglang (openSUSE:Tumbleweed) 0.5.20-1.1 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

SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.

HighCVSS 8.2 · v4.0—No exploit Fix available
Published
Sep 18, 2026
Updated
Sep 24, 2026
EPSS
0.6% · 51th percentile

Report tools

JSON

Action score

32

Monitor

Low priority for now.

CVSS
32 / 40 · 8.2 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · VulnCheck
8.2
NVD has not scored this yet; the score shown is the CNA’s.

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

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-2026-93838

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.

—

Versions reported by the vendor

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

  • sgl-project sglang

    • up to and including 0.5.20affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
openSUSE:Tumbleweedpython-sglangbefore 0.5.20-1.10.5.20-1.1

Same product

sgl-project: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-111391SGLang 0.5.10 through 0.5.22 Code Injection via Debug Dumper Filter
    36Monitor
  • CVE-2026-92972SGLang through 0.5.19 Unauthenticated Route Poisoning via PUT endpoint
    35Monitor
  • CVE-2026-109229SGLang through 0.5.21 Decompression Bomb DoS via NanoNemotronVLImageProcessor
    34Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-7669May 2, 2026 · sgl-project SGLang HuggingFace Transformer hf_transformers_utils.py get_tokenizer code injection
    25Monitor
  • ← EarlierCVE-2026-93688Sep 18, 2026 · SGLang through 0.5.19 Unbounded Memory Allocation via bootstrap_room
    34Monitor
  • Later →CVE-2026-102634Sep 29, 2026 · SGLang through 0.5.20 Denial of Service via Duplicate bootstrap_room
    34Monitor

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
opensuse:python-sglang0.5.20-1.1 · openSUSE:TumbleweedPackage 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.

Variant candidates

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

  • CVE-2026-936880 days apartSGLang through 0.5.19 Unbounded Memory Allocation via bootstrap_room
    34Monitor
  • CVE-2026-10922524 days apartSGLang through 0.5.21 Memory Exhaustion DoS via /v1/audio/transcriptions Upload
    34Monitor
  • CVE-2026-10922724 days apartSGLang through 0.5.21 Memory Exhaustion DoS via Qwen-VL Video Preprocessing
    34Monitor
  • CVE-2026-10922824 days apartSGLang through 0.5.21 Resource Budget Bypass via GLM-V Video Parameters
    34Monitor
  • CVE-2026-11226931 days apartSGLang through 0.5.22 Memory Exhaustion via Unauthenticated Mooncake Decode Registrations
    28Monitor
  • CVE-2026-11227031 days apartSGLang through 0.5.22 Memory Exhaustion via Mooncake STAGING_RSP chunk_idx
    28Monitor

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.
  • No account or password is required.
  • 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
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-770 · Allocation of Resources Without Limits or Throttling

CVSS vector

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

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

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

All records