Malicious PDF — malware analysis report

Static analysis result for SHA-256 b19abf26d2a806dd…

MALICIOUS

PDF

80.2 KB Created: 2021-06-14 10:35:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 0ed26ea847fede1d4282ac4913469ad3 SHA-1: 3b15999c7c8b608869aa0da9a9ac78587ef4dc72 SHA-256: b19abf26d2a806ddf6261c9f291095070d93d49f276134318b403fdb727ba4e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a phishing or malware distribution campaign. The document body, though partially corrupted, appears to be a lure related to an educational worksheet, which is a common tactic for social engineering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://smidgel.ru/uplcv?utm_term=lcm+and+hcf+worksheet+for+class+5 PDF link annotation
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099c0aaa0d4f---36013000349.pdfIn PDF document text
    • http://didopack.com/files/53778726626.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aea10fd65d4---83601812074.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/xekilenowerevuwakij.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b54b83d5cfd---70576216484.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a73dc5dc24f---14874289893.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083555c038f3---walabaxopezobevemo.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210605172749_589379387.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/b0bc7462a9a398a5467385f19238d75a/rixilafuruzekeri.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/58541032233.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f338074aa5---16234923768.pdfIn PDF document text
    • http://www.publicitymailing.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1609251b706288---44316639392.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a3440547cf6---tupekedavowaxadozidiji.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4007eafcb5---10102325086.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f0f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F0 5220 bytes
SHA-256: b1c6527af431f1d2045c39b0659996a807849d4d0224bc77e5dab38b77fd7748
font_01_sfnt_off00010291.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10291 10428 bytes
SHA-256: ccb0706c24787b9a68b4596a98759305447fc45bee8caf6c3c9b346766224c92
font_02_sfnt_off000125c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125C7 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176