Malicious PDF — malware analysis report

Static analysis result for SHA-256 86285a91679b668c…

MALICIOUS

PDF

77.2 KB Created: 2021-07-15 23:48:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fe0eb7eed252bfc07483b351d7b31ab0 SHA-1: 10fc0fdd28f267d3e1d6379683e1a7fc708b2474 SHA-256: 86285a91679b668c6773124acae634fe6efa6c3db0815f2e254918d020641f4d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. The presence of embedded URLs and the nature of the heuristic firings point towards the file being used to redirect users to malicious content, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16084f66fb79c8---91493250554.pdf In PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/7ud0eer04896jcidjvs4bu2424/2079061318.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/mimudijazimitezulutisi.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/b4a515a644f9c8ffde0f7a683bfca259/gexada.pdfIn PDF document text
    • http://dailycan.com/userfiles/files/gubesat.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b800379f0fa---nupiginedosadosebufubole.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc4d74d10b---nijufemavonokumalusa.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/86199214359.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/58ql3q3af5bdjqn159g35htpe2/kodinugaxuratupezumited.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/k4u8mojjpr24aq7aibjou0dltb/57747155323.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e2e6bd1dd---13709104597.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/6c8b7648fd5fcebded7250668a4242c1/8476265023.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/d7c812e9848ea94040db10f2b3a2c016/jajomomaxajolirixupipu.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/dmaued4m7f2f7mtrtun6lsljjj/xozatedatag.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160be2dec41614---xaragifematikefude.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ad10e5178---nexikodezibod.pdfIn PDF document text
    • http://vivo-mebel.ru/upload/file/laxuburanunurujol.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160704ff71c199---11585320368.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/damonisigu.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/7ddhuh21lo68kqqe0s15953r30/87956187542.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c004ae2b5d7---75264010027.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/e14d087653a6d9a89dbfe468d5571aca/sewepaxa.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b292395240---pimanuli.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/71953344913.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b67329ea7---95101662860.pdfIn PDF document text
    • http://logiccpacma.com/ckfinder/userfiles/files/gegoke.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=mike+fisher+cowboysPDF 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_off0000cbb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB3 10448 bytes
SHA-256: 6eb6db3b6984412e4b9a655d5aff09ddcda597ea1d084ed6be2a7dc046076098
font_01_sfnt_off0000e3a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A5 16404 bytes
SHA-256: 110b90dfebeb3238de8f5fac8d1c3e0ced3fb92be27c8477e0c858bed56028f0
font_02_sfnt_off00010e27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1