Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51d7fe41108e337…

MALICIOUS

PDF

81.3 KB Created: 2021-09-20 12:00:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 24b975394f4289d50986365bea6cca96 SHA-1: 5e7cb37fc46bbfb3731eeb9ce64d1f552104786c SHA-256: b51d7fe41108e33763d128cc3124d2bf3b460a31be4d2704b4e248a13d428010
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to malicious content. ClamAV detection and ML classification strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of external URI links and compromised CMS upload links are key indicators of this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://garglob.ru/uplcv?utm_term=how+to+transfer+gallery+from+android+to+android PDF link annotation
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/ce6330f45e8e26458cd0a432835952ef/98639238088.pdfIn PDF document text
    • https://astoraccessories.com/uploads/ckfinder/files/jupit.pdfIn PDF document text
    • https://total-sport.pl/img/upload/files/54016454206.pdfIn PDF document text
    • https://sanaspinler.net/calisma2/files/uploads/xewuti.pdfIn PDF document text
    • http://www.ciesol.es/ckfinder/userfiles/files/32010746173.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/sinuvuxudir.pdfIn PDF document text
    • https://escolaalfa.com/userfiles/file/sojavopama.pdfIn PDF document text
    • http://yeditepegumruk.com/userfiles/nalogofomivizaziduvapexa.pdfIn PDF document text
    • http://nollve.com/img/editor/image/file/78416522923.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/161364bad80813---xodijadak.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312bebe6b84---xuwiretazerejubinox.pdfIn PDF document text
    • http://studiomanzella.com/userfiles/files/sosezoroxemox.pdfIn PDF document text
    • https://pmms-online.com/assets/file/zisabejomoxi.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/283dea5a3e35e1a7c25c99667029c8da/60243094371.pdfIn PDF document text
    • https://bhopalliteraturefestival.com/mpsdp/uploads/files/24592030029.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16133b494d6f84---97226277283.pdfIn PDF document text
    • http://madurastones.com/userfiles/file/fowinutujovufokog.pdfIn PDF document text
    • http://guoyangmoju.com/userfiles/files/ridawilutaxer.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140a43f05cda---panowili.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/92461516421.pdfIn PDF document text
    • https://bangvetthuong.com/luutru/files/53959702179.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_off0000d5a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5A4 18828 bytes
SHA-256: b3ea2ba888fb04b37ccf18bbaf12c9bc842043a7b6137e7055d9e75d80b46af7
font_01_sfnt_off0001063e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1063E 10888 bytes
SHA-256: 1c7c4b4a50fc19f73d251655904308d63e75e55e0e29b021b090254d9041eb29
font_02_sfnt_off00011f3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1