Malicious PDF — malware analysis report

Static analysis result for SHA-256 377b7fcdf57a27cc…

MALICIOUS

PDF

85.5 KB Created: 2021-08-02 17:55:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ba8a44f97deb51b58a00da6cbfaab094 SHA-1: 586bac6b95a42dea8df28a301753b5a32bf6f5f5 SHA-256: 377b7fcdf57a27ccca7f226ed8dbbb39a07861325a33ecc6e187ba12529e44ec
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress upload directories and other disposable domains. This suggests the PDF is intended to lure users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://u15.ch/ckfinder/userfiles/files/zevumuvaxetota.pdf In PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093cf7a6ac98---35352490129.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/mqd0jh7lcog2avptlg5gr8bhqs/vebuxerupuzakapajaveb.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/fe8cab2909484dd641edd9049768c785/38968455222.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4cfec9e601---tojusavow.pdfIn PDF document text
    • http://europavloeren.nl/siteimages/file/20933593383.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/89695840381.pdfIn PDF document text
    • http://cuatro-pr.org/sites/default/files/file/64524643370.pdfIn PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/6e0e4d4f06deb3538bbee9343060851f/sigamadisa.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/xekosav.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160708d0164c9e---27028384912.pdfIn PDF document text
    • http://ugyvednok.hu/userfiles/file/55443431231.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a18aa373388---26592321453.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099f56d76174---sowikavuzorinisutifokap.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/4ef67ed8dff5d888543ed50c55c89fc4/jujepejenaridamafivawike.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160b782464378c---pakipu.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c886bd3eb55---15871830125.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/32441344136.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/ad4cvukaq7sp3hprnts3qbt0cu/35544119685.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/51128843a06c396008eb42f915edf267/kajek.pdfIn PDF document text
    • http://comp-art.ru/userfiles/file/lafelukopaluvosoxekow.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/16586503572.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/sinekenoro.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16076b0ea031d8---marigufunewuwojabosiwifi.pdfIn PDF document text
    • https://www.reflectionuk.com/wp-content/plugins/super-forms/uploads/php/files/lofu164svvvk33rl4c3joqfj2d/nijulubisubukitaraliwalak.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16081bd4a811ce---28253569964.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=tarihi+%C3%A7evre+koruma+ve+restorasyon+zeynep+ahunbay+pdfPDF 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_off0000e500.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE500 11448 bytes
SHA-256: 85a11dd2f9dbcf1fb64f174bf81c0303fd970fda34e2336f472fd1b37741ecdc
font_01_sfnt_off0000ffc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC0 18568 bytes
SHA-256: f97758e83a1166a77faab8948bf14377a86dd11348262dc2810e2b2a0705eaed
font_02_sfnt_off00012d85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1