Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b008f83022e1dd…

MALICIOUS

PDF

82.5 KB Created: 2021-08-22 03:33:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1ec34f2e048779ea58cab75a42ba5aba SHA-1: c69d2a65048687acbf790852290c38c7ee903089 SHA-256: 39b008f83022e1ddf8b274d9480b291a0b552a75a1e9aa2124cc621174014cb8
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The embedded URLs suggest a tactic to manipulate search engine results or redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/1bcadf4f7152cb36008f56406eaa472e/lokonamirekasonukuze.pdf
    • http://duetsepolno.pl/userfiles/file/9378084497.pdf
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092ba457747f---zimumeluzegavefo.pdf
    • http://wrhs1967.org/clients/6/61/617565fc8afb9cc6d18abf932d248b7a/File/xesiraveraxa.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160987662e369a---18545806450.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074aca653fc8---52422476304.pdf
    • https://citronixdeflection.com/nbloom/fckuploads/file/27774756340.pdf
    • http://vita24h.com/uploads/userfiles/file/kemedupufisidexofedumodo.pdf
    • http://sbstroy53.ru/img/files/fajiwupan.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/p2mvos1u1m734sg64npuli8dn8/75201563730.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1610dbbd069eb2---xanuribosufigifumifo.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/1a435685e11bc2607c1b300ab747044c/29287561698.pdf
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/afvpr4ajt62jqgs9h78ddo2360/lavevizovofurikudi.pdf
    • https://gea99.com/ckfinder/userfiles/files/nividipuluxoguropat.pdf
    • https://xo-sound.ru/userfiles/file/4009614904.pdf
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/bbv9cd38n7972u83frmpu89ua4/kewerabijugoterevimojudag.pdf
    • http://chrisdepanneservices.fr/Sites/cds/files/22457855308.pdf
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/9f5800478abcb04ecc7ed70afd03fc30/19771520728.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1608697cd6355e---fufalufetivozu.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ce4bb5739---10958773169.pdf
    • http://gocep.org/data/userfiles/files/19596683564.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/bcomjh92bn5u8m33tr2trmmufo/lonuropuvuxujuzilu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=fundamentals+of+database+systems+6th+edition+solutions+manual+pdf
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/03cbdaab4fde91d48dcaf099fab287ca/wutibefivikikefa.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://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_off0000dc73.bin
9cac186fd836c9f71da1614e655548c71fe294a9294b70316f021b0ca16ebab3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC73 11164 bytes
font_01_sfnt_off0000f62a.bin
c11a0347e0f1f4222b247dc8ea548e5642c0ff0e23b349eb957689bf6d083a9e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF62A 17048 bytes
font_02_sfnt_off000122d0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122D0 16792 bytes