Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dc7764c325c6dac…

MALICIOUS

PDF

78.4 KB Created: 2021-04-19 23:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 0dbc5e18ed55d02fd75db2ed917655db SHA-1: d919837c2fd31f0ab929915118df708f6a9bfeb6 SHA-256: 4dc7764c325c6dac78cc7924a73b09b1f2f29f01aeb4fa767f9e7de3dc5e2429
126 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains or link farms, suggests a phishing or credential harvesting campaign. Although no scripts were explicitly extracted, the PDF structure and embedded links are consistent with techniques used to deliver malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.enwidth.com/sites/default/files/webform/resumes/95374483905.pdf In PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/64517041799.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/bukitonixoravutewoluba.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/dizage.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/80411930416.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/kafavepovimurajubek.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/95941620813.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/viwiredozilopuvotudulufez.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/nunemoxajusadokuxilebe.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/47965191786.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/36759883892.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=uglies+scott+westerfeld+movie+trailerPDF link annotation
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/pitoripizebareko.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/53252105934.pdfIn PDF document text
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C8 5168 bytes
SHA-256: ae63c6586b645df989fefe9be3306fba317790fe6c8f514be3f2dffbdc341dae
font_01_sfnt_off0000f774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF774 11056 bytes
SHA-256: 5dd9199c765bb994058cfc20d45160a5974ecb44c47bc12b28b2860108b2175a
font_02_sfnt_off00011d3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D3B 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176