Malicious PDF — malware analysis report

Static analysis result for SHA-256 137f37a379f60a02…

MALICIOUS

PDF

89.8 KB Created: 2021-07-21 18:17:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 2caa4f587e3af1d2708b6f40ba84952c SHA-1: 73c885c7366c3fe3a99b4e9126332836558226c8 SHA-256: 137f37a379f60a023ec5158a969e03eb7b19f81618420e60c404a686fb3f7a58
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of external URIs and link farms points towards a tactic of directing users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e307a70e20---godoraxefuvefaratom.pdf In PDF document text
    • http://assushop.com/userfiles/assushop.com/file/gogazuwidojitujof.pdfIn PDF document text
    • https://assignmentmart.com/ckfinder/userfiles/files/dotorixawevukanibokedizo.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/56215594369.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d7e9239203---54981360781.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/5q33f3jjeodcpc0d5uavlb1oj4/devolatumulafata.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/3frtn9d5rvoo9oi4ssap915sq4/miponejop.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/a62bm1l1r5h7m6forossgcauge/18021077059.pdfIn PDF document text
    • http://apartmaji-zunicmile.com/uporabnik/file/gamitelixunebexixox.pdfIn PDF document text
    • http://luingpyrex.cz/foto/Image/file/riropalanowujujogulej.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/675d5ca2260dc3e0c837749f27fd7cb8/50712665591.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/wupomenunezotalugojexi.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/37014979653.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/69006670408.pdfIn PDF document text
    • http://cementfeet.com/userfiles/file/jofiwunumapubom.pdfIn PDF document text
    • http://didula.com/img/file/soduxutawosolegetazuzupi.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a58a93c5b19---nulemezisaner.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/d6f5b095f14b6624756d69bb17d7c2fe/31861985826.pdfIn PDF document text
    • http://arenabilardo.com/data/_files/41404594428.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c459711c198---38404490654.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6f7950b73---tokevasuxaler.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160832f7a5bcf0---rebiwuxeredaguned.pdfIn PDF document text
    • http://wernitznigg.at/files/16157507957.pdfIn PDF document text
    • https://najarshi.com/basefile/najarshicom/files/rogibokutavarab.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/basepasogelarok.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160727eef7bfc8---jujixubogigireduso.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/37420270314.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=insidious+chapter+3+demonPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f76e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF76E 10956 bytes
SHA-256: bb5c3041fb43c5e26d5dc85882096e5712faed6ad66b8ebf4c582647463161ee
font_01_sfnt_off000110b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B2 17804 bytes
SHA-256: d8dc2a5ebbd247a9de1a1625b22e75f3ec09ff8071be4071a2c6ea10489b94ed
font_02_sfnt_off00013eb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1