Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca1b987e433e4980…

MALICIOUS

PDF

84.0 KB Created: 2021-07-10 01:53:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1be6a6c62d5eac19d4bd45d15f8d0ba0 SHA-1: 6a7156b572a4a0385c8fbf171e84d6f00c8eed13 SHA-256: ca1b987e433e498007f2b2a2ddc83ba888a3b9bf78955fa21f7203a403e66127
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. No scripts were extracted, but the PDF structure itself is indicative of a lure to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://synerhu.ru/uplcv?utm_term=interview+strengths+and+weaknesses+list
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/xuxakupagagaliritogi.pdf
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/63118089522.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090e39c3de96---mabezorofim.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160d21923228d6---xozudexefofa.pdf
    • https://aplusadvance.com/naver_editor/data/file/2326558260.pdf
    • http://157.230.241.115/image/upload/File/zuval.pdf
    • http://diclenakliyat.com/userfiles/file/3875345258.pdf
    • http://anhbanglaw.com/userfiles/file/70584593322.pdf
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/9kb7lvph5i4k25mnq9ctpdijqt/16643492295.pdf
    • http://emotionpicturesfestival.gr/userfiles/file/fegoliwoserazubutikani.pdf
    • https://biomedchita.ru/imeg_master/file/wisadufodebipis.pdf
    • http://www.greenbriarpropmgmt.com/wp-content/plugins/super-forms/uploads/php/files/a1236978602bad0e76d55faeed8c2dea/xurepunagotibipoximikexu.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/77d13740c36c1be4c71c4e7dff5145b8/37959484764.pdf
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/aacdc5ed6f9b60e914d53a76a456f650/87663564774.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/of5d2qqd7pj9ot0hn6n7q8a1lv/pulemij.pdf
    • http://thegreenlegacykeepers.com/clients/e/e8/e8dc17949b7ef813e9937e453902477f/File/gerokidagaf.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-5-11/20210511192911743564.pdf
    • http://romengo.com/ckfinder/userfiles/files/80342248390.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607092f34348c---memus.pdf
    • https://tonymusic.se/UserFiles/files/xapelib.pdf
    • http://stylekd.ru/files/nemawarekenovumedimogavoj.pdf
    • http://portalkucharski.pl/app/webroot/media/files/lapazuganaxiwi.pdf
    • 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_off0000e828.bin
088325066959e64a76b2f997a3fd879319bdf7e2f7883d5b809671c6e3e33f4f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE828 16532 bytes
font_01_sfnt_off000112ef.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x112EF 16792 bytes
font_02_sfnt_off00012b06.bin
b73ad541e17d432b0fe28c2034023e3b9a15009de9ad8a3f4e635ad0f4955711
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B06 10600 bytes