Malicious PDF — malware analysis report

Static analysis result for SHA-256 fff91ccc683bf9ff…

MALICIOUS

PDF

88.5 KB Created: 2021-04-07 19:31:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8edbc44f41ec6357ea4e176707683a87 SHA-1: 4b5b8ee309dcdfa54c69e97b355b539862c23ba5 SHA-256: fff91ccc683bf9ff0ef858f534767f16e951e8d2f823e3b2c46980119239eb97
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and a machine learning classifier, exhibiting characteristics of a phishing or SEO-based attack. It contains a large number of external links, many pointing to PDF files hosted on Weebly, suggesting a link farm or content distribution network for malicious payloads. The document body is heavily obfuscated, preventing a clear understanding of its immediate purpose beyond the lure of a safety data sheet.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://resalured.ru/123?utm_term=nalco+7330+safety+data+sheet
    • https://zumikifekov.weebly.com/uploads/1/3/0/8/130813997/1176245.pdf
    • https://kedefakoriwo.weebly.com/uploads/1/3/1/1/131164231/8685a36675691c2.pdf
    • https://menolalosixoj.weebly.com/uploads/1/3/4/7/134714047/sarudizumiro.pdf
    • https://dewanuraxode.weebly.com/uploads/1/3/4/3/134324700/fidatolepuvepivo.pdf
    • https://bopidojosonek.weebly.com/uploads/1/3/1/3/131384153/6534381.pdf
    • https://zoponexe.weebly.com/uploads/1/3/1/6/131606878/3772770.pdf
    • http://budivev.scienceontheweb.net/orthographic_drawing_examples.pdf
    • https://kuxivudu.weebly.com/uploads/1/3/0/8/130813582/4771071.pdf
    • https://serutoposax.weebly.com/uploads/1/3/5/3/135398922/silabezokiku-ritizewomi.pdf
    • https://bomoturu.weebly.com/uploads/1/3/1/3/131384468/9069108.pdf
    • https://pafufido.weebly.com/uploads/1/3/1/4/131407890/tekokamifitudojex.pdf
    • https://bemozepe.weebly.com/uploads/1/3/0/7/130739793/naxidevisi.pdf
    • https://kazumole.weebly.com/uploads/1/3/1/4/131454435/2aff71f0bcb9043.pdf
    • https://lalojitewimagix.weebly.com/uploads/1/3/5/3/135304200/cf8e0.pdf
    • http://raxawevamavox.getenjoyment.net/countable_and_uncountable_nouns_definition.pdf
    • https://fekazivijiwawad.weebly.com/uploads/1/3/4/6/134687088/a46fa45c0.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/dudurat/awesome_font_for_windows.pdf
    • https://s3.amazonaws.com/baxekojojexusol/why_is_my_motorola_baby_monitor_not_connecting.pdf
    • http://tikomiwewo.atwebpages.com/reading_comprehension_book_grade_3.pdf
    • https://s3.amazonaws.com/fidobakipivogit/project_x_vs_extended_cut.pdf
    • http://pivimufe.atwebpages.com/lokutogigejemar.pdf
    • https://s3.amazonaws.com/resabomibogodaw/mujegebevujapezurakokaza.pdf
    • https://s3.amazonaws.com/jadudusujuje/14271220951.pdf
    • https://s3.amazonaws.com/widiku/13866036169.pdf
    • https://s3.amazonaws.com/paxuvagal/how_to_apply_intimate_gel.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011d6d.bin
70a6eed0720e1f78fa7e39dfbd4f808243f389774b56c8e0dc916e4365026b87
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6D 5468 bytes
font_01_sfnt_off0001301c.bin
94dec858b8f585425de73b3beae679d8ed0d852661701728f1b65cfc43c2d53d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1301C 10684 bytes