Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe5455bf912942db…

MALICIOUS

PDF

79.0 KB Created: 2021-09-01 04:45:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a922f0f1cd25a03dfcc7cabe675cf642 SHA-1: c8a51c2cb2171931347115322bd38b3ab5b58fd1 SHA-256: fe5455bf912942db2b95d02371f520a47fe7af3b3624a1cf6742b4ca3cf47685
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised WordPress sites or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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 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://irlanc.ru/uplcv?utm_term=demi+give+your+heart+a+break
    • https://avistravel.ro/userfiles/file/14462413116.pdf
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160910ccaaf522---rizabimonaxom.pdf
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/nowupoliwalezimikuterela.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160a90a2373428---geparilekoboposuj.pdf
    • https://iominneapolis.com/wp-content/plugins/super-forms/uploads/php/files/b2f72e890748743f8d1d9be7b8ece274/puwiwu.pdf
    • https://havadisname.com/upload/ckfinder/files/34059143084.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b23e320cf7c---javerasipibemegezawulaka.pdf
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/b64c20c4cba74330b97400fbd04610c4/felavejofudexisaguwes.pdf
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/86109276899.pdf
    • https://alutat.com/data/file/2209022180.pdf
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9541e710f---tewunosazesomamixigimafaf.pdf
    • http://udmvdpo.ru/images/files/vokepovexabogilosonape.pdf
    • https://www.anandtirth.com/wp-content/plugins/super-forms/uploads/php/files/h2sbu8enq7t1h5g1ok706m0r25/76409421135.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759396c61eb---79850122568.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610db52d1acbc---80471661984.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/19f26704ec65b74df1706c109f10ab3a/49819572426.pdf
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/0b441f1e8f86ab82b5801fbe018ba7a0/17183520914.pdf
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160acaa95396a8---kaputetelabapoxenujorad.pdf
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160fbd9ee3d13e---mufajedisukixenal.pdf
    • http://italiangreyhound.pl/img1/userfiles/file/kemolupifikajuneripowegib.pdf
    • http://finproekt-msk.ru/userfiles/file/tudinapitisujelow.pdf
    • http://www.uc-kushiro.net/images/library//File/42966436111.pdf
    • http://akinmedical.com/uploads/file/81110039206.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16088295a18a42---sogupopapiripenep.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_off0000d036.bin
9c990d25b4c9f6f84e5bec28edb2e6d4ed242d00641a36f9af8b3b435ff871f5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD036 10748 bytes
font_01_sfnt_off0000e8ff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8FF 16792 bytes
font_02_sfnt_off00010111.bin
224de97f6bf4b918117f8dbf0bac71549ac79f85d8c871f6e6495c0b08f76433
pdf-font-stream PDF embedded font (sfnt) at offset 0x10111 17324 bytes