Malicious PDF — malware analysis report

Static analysis result for SHA-256 13cf43d2dffd0b53…

MALICIOUS

PDF

79.1 KB Created: 2021-09-19 07:05:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a9d14e249cd2743caef7397e7d9d8de5 SHA-1: eb9ef46ca6c23942ab9ab7d85af43e1a4e77ef09 SHA-256: 13cf43d2dffd0b5361061eb4544f0eeef70ef4ce901267f012d6ad80275ea847
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI indicators and link farm heuristics strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://laborke.ru/uplcv?utm_term=breaking+dawn+part+2+watch+online+fmovies
    • https://cuatudongsaigon.net/uploads/files/dajijaguvapikuruna.pdf
    • https://pasarantogel.com/contents/files/82534221609.pdf
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/62913546067.pdf
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/fikejawagoxiviwa.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/94eead9a962e2ecd96e689d80b26b269/verixupob.pdf
    • http://xn--80aafbjcazdrhzgiddbbcsg4l.xn--p1ai/pict/file/sagapogup.pdf
    • https://simbhaolipower.com/images/file/85945335712.pdf
    • http://gongin.humenia.com/upload/userfiles/2021/09/files/210916102145.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1614564064711f---47612261327.pdf
    • https://ecpa.fr/uploaded/file/42954264282.pdf
    • https://wangwangcamp.com/uploads/files/202109170118048227.pdf
    • http://backkwang.com/userData/board/file/32205216673.pdf
    • https://kar360.com/resimler/files/31492342320.pdf
    • http://heninrealty.com/userfiles/files/kekasolonenuwi.pdf
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/wavopabupelol.pdf
    • http://bakoca.hu/files/file/mikusilevokisunururobun.pdf
    • https://tezerwatch.com/file/upload/files/09-17-21-36-14-33.pdf
    • http://av72-reklama.ru/userfiles/file/16308656744f1fd7e7b0c29be2cf7a.pdf
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/u37sk18ltb7qpqued6m7kcpp97/20486549752.pdf
    • http://fertilityupdates.com/userfiles/files/63486079724.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/ff4a3034d3c38e3cf5728c187839e472/kalopinu.pdf
    • http://www.temaricerca.com/entry2013/admin/ckfinder/userfiles/files/70346662640.pdf
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16143b292eb4fa---59527602198.pdf
    • http://henca.com/files/details/file/89882437206.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_off0000cefd.bin
a35f43595ae27a00092558a20190e0daf3f5379639f57d9e2d4a3a13a5924b4e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEFD 17152 bytes
font_01_sfnt_off0000fb72.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB72 16792 bytes
font_02_sfnt_off00011389.bin
7074bbb6186c537c32dea9af0a168034824bb3b96a8e6bddaa53b047b2f2b8d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11389 11484 bytes