Malicious PDF — malware analysis report

Static analysis result for SHA-256 31a78b9dde4afb8e…

MALICIOUS

PDF

73.8 KB Created: 2021-06-23 04:50:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: c4b9352bd9fc419403190e31716c67d7 SHA-1: f10170cb3f42ef2b6776f92a73feb488a650e8c7 SHA-256: 31a78b9dde4afb8e5d4f5c781c8c4b866290987938b6139c31195b791fef5c14
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS upload directories, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the heuristic firings point to a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8f03375710---55969441902.pdf In PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/54244153921.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/vuxodulafibuzodo.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/mosexodofujawej.pdfIn PDF document text
    • https://antae.be/app/webroot/uploads/file/84599048862.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/ganukotiso.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b616a59737---67793362045.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/55074135206.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b73f0c9431f---lepevagovejubevitul.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/95482273655.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/7e03293ee6748c8ad3ad26055e507257/wumubopuwobitur.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/i31310an9v6lehovfcicso586s/japowopuxoduwekifo.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/fuxagow.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/23135680738.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/2c7faac75b8bf2298a7e99b64d33543e/pijedo.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/dj9bedh1jaq8jlvk86g6pjd20g/21968636596.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=tamil+movies+download+website+listPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e409.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE409 5116 bytes
SHA-256: 9d6d2246a682370a4fd259d6245ed82a4582a3a9e9b188ef53cfabae845a36a9
font_01_sfnt_off0000f571.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF571 10760 bytes
SHA-256: e38f5461dc6ea8e87380c2749cc0e267e7624e02963fd67bb7a6cc427c4a023b