Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f5bc4ec18dc3307…

MALICIOUS

PDF

82.1 KB Created: 2021-09-17 20:37:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 557c6269956ff537ce9f9864b0589969 SHA-1: 224ea2eb694beec254d5cbdde979c2468bc1ad13 SHA-256: 4f5bc4ec18dc330752106025008beba2038f99695533a3caf4c38821c34cebf0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate maliciousness, likely related to phishing or malware distribution. Although no scripts were directly extracted, the structure and embedded links suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://opsir.eu/files/file/84683767951.pdf
    • http://ohadalegistrocbarter.com/ckeditor/uploads/files/lukutonavezakujozoxofowut.pdf
    • http://geteffective.biz/uploadfiles/file/34816983467.pdf
    • http://dichvumucin.com/upload/ckupload/files/xoxosiju.pdf
    • http://accessiblevehicleservices.com/userfiles/file/fetobupukim.pdf
    • http://ricettebiagi.it/uploads/assets/file/42763132099.pdf
    • http://capitolmetrophysicaltherapy.com/files/files/47526337067.pdf
    • http://hansungid.com/userfiles/file/22021470988.pdf
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/64263787551.pdf
    • http://rentaruedas.com/files/others/79651816648.pdf
    • http://oasis-inwaste.asia/files/file/89281591412.pdf
    • https://globalmediaminds.com/uploads/files/15254777252.pdf
    • https://biocoils.com/img/file/73988309658.pdf
    • http://tutek.eu/userfiles/file/38055741393.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16139774f5d321---63258655389.pdf
    • https://its-bulgaria.bg/files/file/lazivunawawe.pdf
    • https://unaizahic.com/Files/files/90182768218.pdf
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/3894848894.pdf
    • http://steelbo.com/uploads/admins/u0/files/20210901135946.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/935cd9f22ba0971cf777c02a0d472763/1838982889.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/8c1a5859404b2e4fc48c02a538b8a6d2/vubax.pdf
    • http://tlca.com/Content/uploads/files/93649089743.pdf
    • https://laznia-radom.pl/userfiles/file/fowipufodunenumumow.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=movierulz+telugu+movies+2021+latest+full+movie
    • 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_off0000d911.bin
af8355850385ad8e75527bfcfc48379a48e985b58ed47ec26d1d12ec558fbbf1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD911 10968 bytes
font_01_sfnt_off0000f2c0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C0 16792 bytes
font_02_sfnt_off00010ad2.bin
fd129faa5003fab652a392d59eae4437a9c97bb01dc4dbd35f9b0f408497abfa
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AD2 18428 bytes