Malicious PDF — malware analysis report

Static analysis result for SHA-256 de63f5b0170f13c3…

MALICIOUS

PDF

92.1 KB Created: 2021-06-30 23:06:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6e1d10fd859ad9bde61306c340690cc9 SHA-1: 81314c5516273d06dda713aadb9a2d9eedfd9f3b SHA-256: de63f5b0170f13c32c01aa2396750d2af5ee6d441b139be06f18dbb6c8edb7dd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure but reinforcing the malicious nature indicated by the heuristics and URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/smcliqs7g7qo58m26a2h5crilb/bevexexixabeno.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/tur4uhtth80b7us1opfue39ug8/71158551540.pdf
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/gbjdlegrve1gm8av04lpgva84r/kejodesugobapukizadut.pdf
    • https://planet-for-events.de/userfiles/file/25105177717.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/c11cdc7cc07f8beb3dde1bc49d8b93b7/sujizuxikorabamixun.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098463852a7a---87416765820.pdf
    • https://yellowstonewildlife.com/fawaf.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/i6tc1teanmdnj3j79ja2a9sshc/zibowoxigemanozoluwuto.pdf
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/0237f09709dcaac242a0932a10a88f5f/rilariv.pdf
    • http://yokohama-model.com/userfiles/files/35859449354.pdf
    • http://urbanconstructions.org/images/uploadedimages/file/fizokira.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c55f022c36---xaparigesuluviboma.pdf
    • https://bio-obst-und-gemuese.de/userfiles/file/3470142095.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b834f9b581f---denefaxu.pdf
    • http://ottotech.center/userfiles/file/45196143162.pdf
    • http://ekolojikweb.net/upld/userfiles/file/49695034685.pdf
    • http://carszana.com/image/upload/File/41641441736.pdf
    • http://ibb-online.ru/f/file/11950115343.pdf
    • http://vantaibactrungnam.vn/upload/files/86094639786.pdf
    • http://associatedreclaimed.com/userfiles/files/4908202288.pdf
    • http://robbes.nl/media/files/83182288512.pdf
    • http://aggengr.com/uploads/CMS/file/xinawa.pdf
    • http://cadeco.com/testingsites/advantage_aviation/assets/media/file/titimuvafosizeb.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=secretary+department+of+higher+education
    • 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_off000103e5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103E5 16792 bytes
font_01_sfnt_off00011bfc.bin
55714c0d7367e984ce44cedc6b38d544e84f0f8e7687781a7c40ff96f8942cd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BFC 11140 bytes
font_02_sfnt_off000135a6.bin
b7b5741f8937134fcfce5658c0656362e4bfc7f287ff2695e696570361107bb1
pdf-font-stream PDF embedded font (sfnt) at offset 0x135A6 17384 bytes