Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f491bf4d160eea9…

MALICIOUS

PDF

80.6 KB Created: 2021-09-14 07:22:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 622c3abbd11681ba3b735e402b395e4e SHA-1: e80df799319663ef22e094865439258f35c115a9 SHA-256: 3f491bf4d160eea91afe678772f0a043814f653b7ee6014df75cfdf4c3941927
126 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically points to a link farm structure with numerous distinct hosts, suggesting a phishing or malware distribution campaign. The embedded URLs, despite some being marked as benign, contribute to the overall pattern of directing users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://apartmani-mestrovic-krk.hr/files/17917505574.pdf
    • https://ruedi-leuthold.com/userfiles/files/9571082715.pdf
    • https://xcheck.vn/uploads/userfiles/file/39378808809.pdf
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/56855838205.pdf
    • http://tramtronbetong.com/uploads/userfiles/file/80681877716.pdf
    • https://nguyenthelong.net/userfiles/files/60388837468.pdf
    • http://ncteonline.com/userfiles/file/69837354230.pdf
    • http://www.mustwalge.ee/data/content/files/17996095226.pdf
    • https://cafesca.info/ckfinder/userfiles/files/95016694659.pdf
    • https://ketdoanbus.com/webroot/img/files/89434470529.pdf
    • https://cartolmania.it/file/22878384186.pdf
    • http://daejonggyoyc.com/userfiles/file/20210910191126.pdf
    • https://bartonsteel.com/tony/barton/ckfinder/userfiles/files/29312292405.pdf
    • http://www.drivingschool-brno.cz/files/files/88056147962.pdf
    • http://kingsfci.com/userfiles/file/49444709213.pdf
    • https://5703n1n6999-6a55.com/contents/files/fotomelumisakezasuxarag.pdf
    • http://1000projects.ru/upload_picture/file/69032106253.pdf
    • http://abcbyspu.com/ckfinder/images_store/files/44715450452.pdf
    • http://tfh-filter.hu/_user/file/92262786442.pdf
    • https://sanagustin.cl/files/belibodatojezixisevowo.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c50527aac1---kakofuja.pdf
    • http://oodow.cn/upload/file/21091322434128663300cta2g9xyrc.pdf
    • http://newshop.jp/archive/file/zizuzizuji.pdf
    • https://dodatnagarancija.com/userfiles/file/1247408266.pdf
    • https://detectagsafety.com/ckfinder/userfiles/files/siginaviberemup.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=no+script+chrome+android
    • 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_off0000d83f.bin
edc6cd3ed414683d3a35cb0031405e1151aa47be0be064ded020d10cada1bdac		 pdf-font-stream PDF embedded font (sfnt) at offset 0xD83F 10712 bytes
font_01_sfnt_off0000f0ad.bin
dbc36ea58e317cdc48b9cb91d10c4138b7e58c3c5b99d2795f9a8f3826608846		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF0AD 17312 bytes
font_02_sfnt_off00011d48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0x11D48 16792 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.