Malicious PDF — malware analysis report

Static analysis result for SHA-256 65f5c7bbfcf8c676…

MALICIOUS

PDF

94.4 KB Created: 2021-08-03 16:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 68f134a03e74736eef983013e6bf932d SHA-1: fad6e09ff65edba7b55568deda7262dd29244ad1 SHA-256: 65f5c7bbfcf8c676f0d459467a37e5de64d7033f2f24c674825810209e9d76bd
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous external URIs and link farm patterns, with many pointing to compromised WordPress sites or disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://udruga-invalida.hr/files/10901888463.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b228af2cb3f---sevupigoxilenujuxogi.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c968de47fc9---moxonijuzajug.pdf
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/l51dvjerqhqnhaf7j0llgk034i/lalaxipizorex.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e64fe64e3de---nezezimubimukisabuvorula.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799e07707fb---53474631527.pdf
    • https://etonbio.com/newsLetters/images/file/71115349371.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082ec9d967c5---metotipekejivufagatanizos.pdf
    • https://paklya.su/design/img/upload/file/10556741396.pdf
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/f6aju4hk199uv1gsuf4q7b1jj7/25450960877.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/0minv195m3m4a0u1jtb63q3kc3/69090791124.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/8c4a80778879f0c63030647a54203057/82723742270.pdf
    • http://tikatalog.sk/_files/file/gitavoxaxoxirido.pdf
    • http://bendhorseride.com/userfiles/file/xoxuzodatorenilif.pdf
    • http://domgr11.ru/uploads/files/90563359110.pdf
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/7ip238odjfn31ugoep9o2sjka1/13570208503.pdf
    • http://mtjjt.com/2013/upload/article/files/2107141409569514505vret.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/346ea6e6403fb79cf3cbb0aa9686d461/kunuzinufamipeledexo.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/mjak3tjppibvb20838fsu4ord5/venenoniparam.pdf
    • http://arisutour.com/ckupload/files/54416415499.pdf
    • http://birzebbugastpetersfc.com/files/file/wexuzekodivigibewafig.pdf
    • https://xo-sound.ru/userfiles/file/79677452772.pdf
    • https://jhservice.net/imagenes/galeria/files/giriwotew.pdf
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/isu7a69fff0gg99ipvhsmmd9s1/fejebarasawefowuxaj.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=how+to+get+out+of+elo+hell+overwatch
    • 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_off00010bd5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD5 16792 bytes
font_01_sfnt_off000123ec.bin
cfca8aaf66f252e404ee6dab1aef29972be2923a4c70c0257aa40a6e0ce183ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x123EC 10496 bytes
font_02_sfnt_off00013c08.bin
07636e56b52a43255e795c7132dd426f05971709809402a8a71b2be6407bf6e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C08 17384 bytes