Malicious PDF — malware analysis report

Static analysis result for SHA-256 6112fc388deee721…

MALICIOUS

PDF

87.1 KB Created: 2021-06-30 20:59:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e944ff3d49c45a9f375b79afef0b4d1c SHA-1: bb313c5eb8ebc13f1d39ed612a1d351a76892626 SHA-256: 6112fc388deee72105d34d7a8ebbd228a233e2e8fe36cea35d058114092a67eb
136 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1539 Steal Application Data

The PDF was flagged by an ML classifier as malicious and contains heuristics indicating it is a link farm and an MFA/one-time-code harvesting lure. The document body is heavily obfuscated, preventing a clear understanding of its direct content, but the heuristics strongly suggest a phishing attempt to steal credentials or session tokens. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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 http://brenno-tojestto.pl/userfiles/file/39245550787.pdf
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/8c10ec28e19185692430979056326f92/xapobimikonediwopafaridi.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608ac41c43f5b---bobofurujutu.pdf
    • http://lapenya.cat/imgjovesnaves/file/79543616556.pdf
    • http://noithatnhapkhaugiasi.com/luutru/files/sepis.pdf
    • https://abicecream.ru/ckfinder/userfiles/files/8413784991.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160927ccdd9971---tawivoto.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c62d82fe2c---ragotaraveme.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/e5fi1vhsgj17gqvuispromcif4/56219491773.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/ffc985ecb2cbedfc56ca91a361603a61/vemesevuva.pdf
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/b2an4j3sip1v90ldi2vl1m1hs7/widuxixirewafuj.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608192017ab51---zaritir.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607383436b477---vovavexadomokesedorajopo.pdf
    • http://apsencollege.org/test/fckeditor/file/komokawumubeti.pdf
    • https://chokysitohang.com/Uploads/userfiles/files/43670142228.pdf
    • https://ratsimae.eemedia/contents/file/danes.pdf
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/8a7cb81af35399dadd684801a60c58f0/53303204683.pdf
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/2fcd04a84057392eb281aefe47ee11e8/33582148953.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/1c71c4ff191aecd17aebf033b7f1df3a/melew.pdf
    • https://dotcomtravelegypt.com/userfiles/files/92709330589.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/t760sbjr3eq1n6imh6uj14kpg0/31468186123.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/vp5lb1emf612nuifh9v5ejcaie/27327880867.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=when+do+cats+lose+their+milk+teeth
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f398.bin
fe473473cf3d385281d328ca75155bc847e87b0470cdf5492d82577f524a65a6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF398 10720 bytes
font_01_sfnt_off00010c05.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C05 16792 bytes
font_02_sfnt_off00012417.bin
94d59784cf549f1cfc417a0bbbcf76ed6e318fb540dd291f4dc79fb702a2d546
pdf-font-stream PDF embedded font (sfnt) at offset 0x12417 16564 bytes