CVE-2026-28318 (GCVE-0-2026-28318)
Vulnerability from cvelistv5 – Published: 2026-06-04 14:05 – Updated: 2026-06-06 03:55Title
SolarWinds Serv-U Unauthenticated Denial of Service Vulnerability
Summary
SolarWinds Serv-U is susceptible to specially crafted POST requests that crash the Serv-U service without authentication using Content-Encoding: deflate. Mitigation steps are provided to secure customer environments in the SolarWinds Trust Center if you are unable to deploy the update
Severity
7.5 (High)
SSVC
Exploitation: active
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-05 00:00 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
3 references
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| SolarWinds | Serv-U |
Affected:
15.5.4 and previous versions
|
guessed |
CISA
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: b00d5422-d924-4e37-a319-af4fa11ed523
Exploited: Yes
Timestamps
First Seen: 2026-06-05
Asserted: 2026-06-05
Scope
Notes: KEV entry: SolarWinds Serv-U Uncontrolled Resource Consumption Vulnerability | Affected: SolarWinds / Serv-U | Description: SolarWinds Serv-U contains an uncontrolled resource consumption vulnerability that allows specially crafted POST requests using the Content-Encoding: deflate header to crash the Serv-U service without authentication. | Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. | Due date: 2026-06-19 | Known ransomware campaign use (KEV): Unknown | Notes (KEV): https://www.solarwinds.com/trust-center/security-advisories/cve-2026-28318 ; https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_15-5-4-hotfix-1_release_notes.htm#link7 ; https://nvd.nist.gov/vuln/detail/CVE-2026-28318
Evidence
Type: Vendor Report
Signal: Successful Exploitation
Confidence: 80%
Source: cisa-kev
Details
| Cwes | CWE-400 |
|---|---|
| Feed | CISA Known Exploited Vulnerabilities Catalog |
| Product | Serv-U |
| Due Date | 2026-06-19 |
| Date Added | 2026-06-05 |
| Vendorproject | SolarWinds |
| Vulnerabilityname | SolarWinds Serv-U Uncontrolled Resource Consumption Vulnerability |
| Knownransomwarecampaignuse | Unknown |
References
Created: 2026-06-05 18:00 UTC
| Updated: 2026-06-05 18:00 UTC
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 0ab957d4-f6b3-43d3-a77c-8866fbe67fcb
Exploited: Yes
Timestamps
First Seen: 2026-06-05
Asserted: 2026-06-05
Scope
Notes: KEVIntel entry: SolarWinds Serv-U Unauthenticated Denial of Service Vulnerability | Affected: SolarWinds / Serv-U | CVSS: 7.5 (HIGH) | EPSS: 0.01054 | Used in malware: unknown | Not yet in CISA KEV: False
Evidence
Type: Public Report
Signal: Successful Exploitation
Confidence: 70%
Source: kevintel
Details
| Feed | KEVIntel (kevintel.com) |
|---|---|
| Title | SolarWinds Serv-U Unauthenticated Denial of Service Vulnerability |
| Vendor | SolarWinds |
| Product | Serv-U |
| Added Date | 2026-06-05T18:00:36.180Z |
| Cvss Score | 7.5 |
| Epss Score | 0.01054 |
| Cvss Severity | HIGH |
| Epss Percentile | 0.59929 |
| Used In Malware | unknown |
| Ahead Of Cisa Kev | None |
| Not Yet In Cisa Kev | False |
References
Created: 2026-06-23 14:03 UTC
| Updated: 2026-07-10 06:14 UTC
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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