Malicious PDF — malware analysis report

Static analysis result for SHA-256 a35e59bdb151ff45…

MALICIOUS

PDF

84.7 KB Created: 2021-10-09 10:10:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d53f4ed329e468b9b1a10c6110ad866c SHA-1: 80acb4d1c7d04bfd59a91da75f64ba29e6f846b4 SHA-256: a35e59bdb151ff4590a466a776a6f414988cd3341105b6ec20a7c9de265595b1
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a high heuristic score indicating it's part of a link farm on disposable hosting. ClamAV and ML classifiers confirm its malicious nature, specifically flagging it as a phishing trojan. The file likely serves as a lure to direct users to malicious content hosted on these external domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141df1075b14---42921833138.pdf In PDF document text
    • https://xn--interpeas-r6a.es/upload/files/luxugagutotofoxog.pdfIn PDF document text
    • https://twinslock.com/ckfinder/userfiles/files/43290384342.pdfIn PDF document text
    • https://euchebnici.com/img/file/xezeresefemolinas.pdfIn PDF document text
    • http://compsult.net/userfiles/file/sirolikuwosusajux.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/forepe.pdfIn PDF document text
    • http://valentine.tutaylamhet.com/storage/ckfinder/files/foseseg.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/97982410404.pdfIn PDF document text
    • http://commandhousecreations.com/uploads/files/garutejure.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7b7a3134b---4828000109.pdfIn PDF document text
    • http://byecook.com/ckupload/files/29578170076.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/26389829724.pdfIn PDF document text
    • https://maviet.vn/upload/files/20452866202.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/77668028073.pdfIn PDF document text
    • http://supragyn.cz/userfiles/file/ralami.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/noxiwutolenasedagupomud.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/nunozivoxumaj.pdfIn PDF document text
    • http://akvarium-olbrecht.cz/upload/file/14323792818.pdfIn PDF document text
    • https://ud-hobby.com/images/Upload/file/mowakobodipa.pdfIn PDF document text
    • http://laclonghotel.vn/upload/files/45058237925.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210919165406.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/fofajolekijasebonema.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/2887129824.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=thinking+highly+of+someonePDF 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_off0000e4f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD07 18636 bytes
SHA-256: 9de08bd10b829b3e0454ee08aec76476c516af85f81d1a320394be93ca18f2c8
font_02_sfnt_off00012db1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB1 10468 bytes
SHA-256: 4ffbe0c7f7c6543bd08acf85d3c0690fbbadfded2990b70d9432fc7cb231db51