Malicious PDF — malware analysis report

Static analysis result for SHA-256 4344f45c8c1a2655…

MALICIOUS

PDF

88.0 KB Created: 2021-09-20 14:15:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 05f4dff090cbfa5cc31dbb38afdf311d SHA-1: c999cb544e00e29d6ea864d885e3724b7691d55c SHA-256: 4344f45c8c1a2655a11b9098d7966fdaf9ff3aa865d80a33d3ae42ea05764bc4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs, many hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The presence of embedded JavaScript and ClamAV detection as 'Pdf.Phishing.Trojan' strongly suggests a malicious intent, likely phishing or malware delivery. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://wastran.ru/uplcv?utm_term=kindle+can+read+pdf
    • http://ceramkgres.ru/userfiles/file/jowixamobemikux.pdf
    • http://dangkydoanhnghiep.org/hinhanh_fckeditor/file/lukodixitamomixezetapifa.pdf
    • http://staropolski.net/Upload/file/71233244358.pdf
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/xawagosak.pdf
    • https://www.ijestr.com/ckfinder/userfiles/files/vizarasomevukaj.pdf
    • http://termocity.by/pics/files/mugik.pdf
    • http://nuklearmedizin-amro.de/userfiles/file/malezulixilasuxudija.pdf
    • http://lizhechem.com/upload/files/43298426049.pdf
    • http://daegyung.kr/userfiles/file/20210917213104.pdf
    • http://dga.gr/ILC/img/file/24608268445.pdf
    • http://parentini.it/userfiles/files/88631713711.pdf
    • http://palyavalaszto.hu/teszt/upload/file/86289362783.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfafe9aaa8---41869179907.pdf
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/30346066354.pdf
    • http://eqletstalk.com/uploads/files/202109171953094275.pdf
    • http://nutronicltd.com/userfiles/file/24420260174.pdf
    • http://jiehuist.com/userfiles/files/tipukad.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/6caf780eb04bb954cba2ae6b6b82c614/kejujemag.pdf
    • http://www.fonfe.com/uploads/files/tigagunobozifaxurenateto.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/9e62e0767c4cd7e0dd2656f0e32e6633/pekafubesetojesagavone.pdf
    • http://lakesnwoodskerala.com/uploads/file/sejofixeleromubatona.pdf
    • https://burgaseguros.com/userfiles/file/78899742753.pdf
    • http://metaglas.kr/userData/board/file/11837420127.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_off0000f576.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF576 16792 bytes
font_01_sfnt_off00010d8d.bin
940c34f0b7da39f1a8df972ca3788a498ff05d7004c6b764244ccc14d82a45c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D8D 10216 bytes
font_02_sfnt_off00012474.bin
d41c76ae0e0d8cb48db96750112f7a0c2e91d9718d2e8dff199fcd4691f6ef3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12474 17672 bytes