Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3836085bd927203…

MALICIOUS

PDF

82.8 KB Created: 2021-07-05 00:18:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 7e9968ce0d20b671fea29efe38fd25a8 SHA-1: 3613e1875b36d76645e413348994abdc1ad22643 SHA-256: a3836085bd927203152ded87b7f11cdd770431acb0cf4025f6f20a076d53d5c1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. The presence of numerous links pointing to compromised WordPress sites and disposable hosting suggests a link farm designed to obscure the true malicious destination or distribute malware. ClamAV detection as 'Pdf.Phishing.Trojan' further supports the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://honghow.com/ckfinder/userfiles/files/62666474558.pdf In PDF document text
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/9a93b7b001360600b8fc829b9cc39e49/44083024825.pdfIn PDF document text
    • https://hagepoorter.be/files/files/fajexomavudamugim.pdfIn PDF document text
    • http://cephedanismani.com/images/pages/file/89495291945.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/6943a69057df0c5e0da960bfb59df53e/mitanetosazol.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca7f9df767---wugulekuxaruloj.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/67612308252.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608e2aff32d1b---77060034019.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/39849577876.pdfIn PDF document text
    • http://sk-massimo.com/js/upload/files/jutixe.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/tosomuda.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609684b885224---bimigugezaterijegitesepo.pdfIn PDF document text
    • https://bilegt.mn/userfiles/files/zufagabejobizogujufalabas.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b4cf96f4179---gezevadigaxasarujo.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/1c97595ea0c0beee4224cd6006dbecc5/87932947806.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/4339614553.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/47341105027.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/85420525021.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608cc3d1bf8f7---guletubatol.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/759fnvgidg1gnromuv04bqik61/kerawefewupobobikub.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/gp5bmavlao54mgruh0rdqce3h0/poluposubuzavepif.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e94031969---zorunogivolelijigu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=james+rollins+sigma+force+series+reading+orderPDF 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_off0000e145.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE145 16952 bytes
SHA-256: f140026908e3e595a9496b1701af65b3a801346cb666347d1bccae39cc761aa4
font_01_sfnt_off00010d21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D21 10712 bytes
SHA-256: ca715fc359aaadb115d54d77c2bffc3aef654d7be34c576ad9270e28153d154b
font_02_sfnt_off00012575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12575 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1