Malicious PDF — malware analysis report

Static analysis result for SHA-256 385a13d1ae3da23d…

MALICIOUS

PDF

100.5 KB Created: 2021-09-17 09:14:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 9616ccc603970227383f234b8c672c8c SHA-1: 7086b4ca4267257dc4fe33ddca7d56802b5ef694 SHA-256: 385a13d1ae3da23d68c3d8be3e5d5660252edef449c440d48a032aa8f02ab651
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure points to malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://m3hotels.com/userfiles/file/94966291693.pdf In PDF document text
    • http://pierrevillers.fr/mairie_files/file/97487330601.pdfIn PDF document text
    • https://minlinart.com/archive/upload/files/8199513841.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109171353171385.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/nijipijegew.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613855d6d122f---zufavugejowotizam.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/zorajiwijorufaxesatif.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/dojuvev.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/36960310975.pdfIn PDF document text
    • http://zpkprzemysl.pl/ckfinder/userfiles/files/wejafijojejuxevoron.pdfIn PDF document text
    • https://myarchitect.es/ckfinder/userfiles/files/fanuzeraxupomofajipowos.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/nosetasaterininiji.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/12983050420.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/kenapemajabikilipe.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/domadogidapipadaxomawixu.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-9-9/20210909155922994796.pdfIn PDF document text
    • https://businesslife.com/content/files/85373789818.pdfIn PDF document text
    • https://clickbox.ro/images/file/7248716043.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613215198ec3f---ginizilemamalurazujawemik.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16130bfa8c7ad1---lobakolujor.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/1153299662613f4d5168bf4.pdfIn PDF document text
    • http://cdn.eagle.mn/uploads/userfiles/files/22412449351.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/5663095353.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=fear+the+walking+dead+season+3+episode+5PDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000120b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120B8 11132 bytes
SHA-256: e88c2f7367230d652cf198869a7f202d8b85e8bdc97aa7ffaf056979fd447970
font_01_sfnt_off00013a88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001529a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1529A 19124 bytes
SHA-256: a20dc17905092bc77d640120ba3089abc678f60b29d036ae191b3858ed2c0db9