Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dc718cc51799e36…

MALICIOUS

PDF

86.6 KB Created: 2021-09-19 19:03:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 291392266b8ff538eb63ceae8756bed4 SHA-1: 56d5fdbee61d741c380aa094eba9777358b0053d SHA-256: 8dc718cc51799e36ba8207fd598051c958fb925503ae168f27a6232cac914517
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Several heuristics point to the document functioning as a link farm, hosting numerous links to potentially compromised websites or disposable domains, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://chokysitohang.com/Uploads/userfiles/files/wexedodatesozetode.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16139eac33619d---nivorelajokuzivi.pdf
    • http://medtravel.pro/images/hand_uploaded/files/48682383217.pdf
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/15did3smentt0p0hv6ihuq469d/52160800840.pdf
    • http://hanasushichoice.com/uploads/files/sujawelojakugorisedolana.pdf
    • https://huuphongplastic.vn/uploads/images/files/39107709257.pdf
    • https://chameleoncoupons.com/adgprocessing/uploads/files/50198698540.pdf
    • http://elrey-uslugi.ru/media/file/joritunagizafituxegiv.pdf
    • https://serviceelectric.ca/userfiles/file/26120066278.pdf
    • https://sunridgecorp.com/uploads/files/202109080312048845.pdf
    • https://preprodpcb.com/userfiles/files/12752239289.pdf
    • https://bushregenerators.biz/userfiles/files/fikanerululuv.pdf
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/lejepaduzapipukapimubub.pdf
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/nififu.pdf
    • http://protradingindia.net/userfiles/file/44520675372.pdf
    • http://dynamic1984.com/user_file/file/99136439577.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/d914db9f7e550e31694a3c148da5902d/rixavuraze.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/161339a0a00f5d---kejalubilazedokilin.pdf
    • http://ucokampen.com/media/files/35201786193.pdf
    • http://sireny.net/share/files/zegebabefinozi.pdf
    • http://deleersnijder-bocaege.be/images/file/sejoken.pdf
    • http://agcslohian.com/userfiles/file/jugobegaj.pdf
    • http://zit-tech.com/userfiles/files/wutas.pdf
    • http://futboltotal.net/images/files/zipoxiwawesegasugalareza.pdf
    • http://alessandrobelleseveterinario.eu/userfiles/files/42314946917.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=iphone+se+2016+price+in+bangladesh
    • 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_off0000e64e.bin
ac95546e80800daf74b728137d74ca4e0b4d68e3b5ee12e1821e11ef7566be68
pdf-font-stream PDF embedded font (sfnt) at offset 0xE64E 11248 bytes
font_01_sfnt_off00010038.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10038 16792 bytes
font_02_sfnt_off0001184a.bin
29d27bcd3e0a2510a898af6d41e4d7681ceaadad5807d7cb23031a2e7fa5f23d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1184A 19832 bytes