Malicious PDF — malware analysis report

Static analysis result for SHA-256 a66e7b5de988e7dd…

MALICIOUS

PDF

9.8 KB Authoring application: %title% First seen: 2026-05-09
MD5: f025f640c34f11760528f70aa2de5b66 SHA-1: 1b0f8840cea44570ae9f4425cdcfbbdcbfbcf325 SHA-256: a66e7b5de988e7ddb50ddef53f4aa74b9fa6199e3a352bec4e0dd1e591907c3d
238 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious File T1204.002 Malicious File: User Execution

The file is a PDF document flagged by multiple heuristics and ClamAV as malicious, specifically identifying it as 'Pdf.Exploit.Agent-36962'. The presence of an embedded file and an XFA form further indicate a potential exploit. The ML classifier also strongly suggests maliciousness. The primary IOC is the ClamAV detection name.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 8

  • ClamAV: Pdf.Exploit.Agent-36962 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36962
  • PDF exploit shellcode contains an embedded download URL high PDF_JS_SHELLCODE_DOWNLOAD_URL
    Decoded PDF exploit shellcode contains a hardcoded http(s) URL — stored as little-endian %uXXXX Unicode escapes, or hex-encoded in a document metadata field (/CreationDate, /Title) and referenced from the decoded script. Reader exploit shellcode embeds the second-stage fetch URL this way and pulls it down with a urlmon/URLDownloadToFile-style download-and-execute (commodity downloader behaviour rather than a specific Acrobat CVE).
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://cash.1step-cashflow.com/score/despite_disappearing_observed.php?qna=31:33:1o:1m:30&ayhnlnly=32:1l:1g:1l:1g:30:1k:1m:1n:2v&ejieva=1i&ccrum=crbisdsp&hegduof=tnxcd Referenced by PDF JavaScript
    • http://www.xfa.org/schema/xfa-locale-set/2.1/In PDF document text
    • http://www.xfa.org/schema/xfa-template/2.2/Referenced by PDF JavaScript
    • http://ns.adobe.com/xdp/In PDF document text
    • http://www.xfa.org/schema/xci/1.0/In PDF document text
    • http://www.xfa.org/schema/xfa-data/1.0/In PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0041.bin pdf-embedded-file PDF EmbeddedFile object 41 at offset 0x111A 85 bytes
SHA-256: c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
embedded_file_obj0042.bin pdf-embedded-file PDF EmbeddedFile object 42 at offset 0x11CC 1029 bytes
SHA-256: dda0835df994b8be920f715db36452f6cee7bb42bbc9c897f878a7b298ba8e91
embedded_file_obj0043.bin pdf-embedded-file PDF EmbeddedFile object 43 at offset 0x13E5 8344 bytes
SHA-256: 312570f1f2cb3898262363f9fabb9f2e7466132bce1e6eded167155418afea18
Detection
ClamAV: Pdf.Exploit.Agent-36962
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
embedded_file_obj0044.bin pdf-embedded-file PDF EmbeddedFile object 44 at offset 0x2408 144 bytes
SHA-256: 3dd68f00f4fcb366a2a3a17c65cb2626eeddf5ea5713302d374310561d810169
embedded_file_obj0045.bin pdf-embedded-file PDF EmbeddedFile object 45 at offset 0x24B4 77 bytes
SHA-256: 10c03f88a5f0a0833dc5b2c8ac295b3a3c6f65e23889eb8cc1dc6fe29bf7f275