Malicious PDF — malware analysis report

Static analysis result for SHA-256 49dd9961ee2558df…

MALICIOUS

PDF

13.02 MB
MD5: 20d282f880fcfb2b3f71f9e28915aa10 SHA-1: 38a2e9f0b1faba24922995155f7a147f1f01f356 SHA-256: 49dd9961ee2558dff9e48e55e0e8a3d58f302cccaf2af00e42eb936cb02c220a
224 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF file contains an embedded JavaScript payload, indicated by the PDF_EMBEDDED_SCRIPT_PAYLOAD heuristic and the presence of a decompressed stream script. This script is likely responsible for executing malicious code, potentially exploiting CVE-2023-26369 as suggested by related heuristics. The file also contains an appended ZIP archive, though it is reported as corrupt, and an unknown reputation URL, suggesting a multi-stage infection process. The ClamAV detection of Win.Exploit.Doublepulsar-7427328-0 further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier clean score 0.0001

Heuristics 8

  • TrueType bitmap font + active content — CVE-2023-26369 related high CVE related PDF_CVE_2023_26369_RELATED
    PDF embeds a TrueType font with bitmap tables (EBDT/sbix/CBDT) alongside exploit delivery indicators — CVE-2023-26369 exploits the sfac_GetSbitBitmap function in Adobe's libCoolType for arbitrary code execution. This CVE was actively exploited in the wild, but this rule does not validate the malformed EBLC/EBDT primitive.
  • ClamAV: Win.Exploit.Doublepulsar-7427328-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Exploit.Doublepulsar-7427328-0
  • Embedded script payload in PDF stream high PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain script execution markers such as ActiveXObject/CreateObject, WScript.Shell, PowerShell, or shell-exec primitives. This is stronger than ordinary PDF JavaScript because it indicates a staged external script payload hidden in stream bytes.
  • PDF with appended ZIP archive high POLYGLOT_PDF_ZIP_APPENDED
    A ZIP local-file header was found AFTER the last %%EOF in this PDF — a polyglot pattern where the same bytes are a valid PDF for a PDF reader and a valid ZIP for an archive parser.
  • Unusually high stream count medium PDF_MANY_STREAMS
    PDF contains 501+ stream objects — may indicate heap spray or heavy obfuscation
  • Corrupt or invalid ZIP archive medium ARCHIVE_CORRUPT
    The file appears to be a ZIP archive but could not be opened. It may be corrupt or deliberately malformed.
  • 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://www.iuqerfsodp9ifjaposdfjhgosurijfaewrwergwea.com
    • http://www.iec.ch
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/pdf/1.3/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • https://docs.microsoft.com/typography/abouthttp://lucasfonts.comMicrosoft
    • http://en.wikipedia.org/wiki/MIT_License
    • http://crl.microsoft.com/pki/crl/products/MicrosoftTimeStampPCA.crl0X
    • http://www.microsoft.com/pki/certs/MicrosoftTimeStampPCA.crt0
    • http://www.microsoft.com/pkiops/crl/MicCodSigPCA2011_2011-07-08.crl0a
    • http://www.microsoft.com/pkiops/certs/MicCodSigPCA2011_2011-07-08.crt0
    • http://crl.microsoft.com/pki/crl/products/microsoftrootcert.crl0T
    • http://www.microsoft.com/pki/certs/MicrosoftRootCert.crt0
    • http://crl.microsoft.com/pki/crl/products/MicRooCerAut2011_2011_03_22.crl0^
    • http://www.microsoft.com/pki/certs/MicRooCerAut2011_2011_03_22.crt0��
    • http://www.microsoft.com/pkiops/docs/primarycps.htm0@
    • http://www.microsoft.com/Typography

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_007_off000f2961.bin
44dcab0c4081928e11a5bb5e1fce0deeb74e0e8c979b6674d041d396459fcdc7		 decompressed-pdf-stream PDF FlateDecoded stream at offset 0xF2961 1510299 bytes
stream_013_off00129318.bin
56ebbc07664a188e0e1489f4fff62b76dc637e2cc7373ba1432441c96d47b042		 decompressed-pdf-stream PDF FlateDecoded stream at offset 0x129318 60372 bytes
stream_021_off00139e32.bin
0e2d7155f9847bcb5a38b1656a7beae6e36a39b10f7271f59cb5c76e19eb6fe7		 decompressed-pdf-stream PDF FlateDecoded stream at offset 0x139E32 163080 bytes
stream_030_off007e45ad.bin
9bb3a307a31ddc6a02b6b8a469e9668b8bc06950c2eb8e9580a310bb10714cba		 decompressed-pdf-stream PDF FlateDecoded stream at offset 0x7E45AD 116852 bytes
embedded_pdf_script_00844ac2.bin
09a517fa5e2bfd798ea5e6cc586d956fe6e2d11ac3eb99d8df25f4758bbe7831		 pdf-embedded-script PDF decompressed stream script payload at offset 0x844AC2 8388608 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 long base64-like blob(s).

Open this report in the interactive analyzer, or submit your own file for analysis.