Malicious PDF — malware analysis report

Static analysis result for SHA-256 737d24af9a4e1a84…

MALICIOUS

PDF

88.1 KB Created: 2021-06-29 20:51:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 645b0a9777b0588123ec490174ede4b5 SHA-1: 4787630e46837a2f1f05c29e15f00fa02ca2c44c SHA-256: 737d24af9a4e1a84b5498544ef746b11c795c4c3397ba1a6a83c7d1242ea9e17
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, which in turn host other malicious PDFs. This suggests a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. No scripts were extracted, but the structure of the PDF and its embedded URLs are indicative of a link farm designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://archism.ru/uplcv?utm_term=different+paladin+oaths+5e PDF link annotation
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16078a37a694ab---22482820538.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e262a1f739---tufiso.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/78f98ca5dac58cfa4b7c6679d289f3e1/28840566161.pdfIn PDF document text
    • https://bangprice.com/bangprice.com/beta/cms_image/file/kawajiresigawo.pdfIn PDF document text
    • https://andrejc.si/files/file/77488613125.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/50634276477.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/noniwanaxaketiko.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da3e74961a2---xikejuwesi.pdfIn PDF document text
    • https://castilloexterior.org/ckfinder/userfiles/files/99884298097.pdfIn PDF document text
    • http://anapharmata.hu/ckfinder/core/connector/php/files/42154565441.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/10203913961.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/pitulogesofedaxazo.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16072198e82318---jasokenupibag.pdfIn PDF document text
    • https://hpsoft.shop/upload/files/gikefusesalavugurugapes.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b321ce3884---japubomulajuxiwilezukigu.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/6734569717.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5d5e78f15---xoxon.pdfIn PDF document text
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/nimowevinogabebo.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607db106c0a07---44399971762.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/a27718131bd048f7be9864c3db92a2b1/tenotubesavadupinoni.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/d24d449c2f83c9901b0faa1210b106fb/31684275094.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/lole354cs89cv3e2i1jlma8vqp/redogijirekinafonadox.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/74202061259.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c85e40085d8---feronemonegu.pdfIn PDF document text
    • 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_off0000f522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF522 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D34 17204 bytes
SHA-256: 409d63c7cc52bc117d709f4d80a2ffab173e708fc74169684e8fcfbeb1a71c5e
font_02_sfnt_off00013a86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A86 10728 bytes
SHA-256: fdbc604619bc5a3b454b6ff7448f984e668b58f9ebcb63757c2bf41ca9eaefe1