Malicious PDF — malware analysis report

Static analysis result for SHA-256 624f6d0268167788…

MALICIOUS

PDF

89.5 KB Created: 2021-09-16 18:25:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 184467a827914441915d40623d5f42ab SHA-1: 5697b064f192326bc7367b17e019d112e097331a SHA-256: 624f6d0268167788781cccf8f9634f85e18b7ea4e589cf49a5b81e4df88167c4
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059 Command and Scripting Interpreter T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating malicious intent, including a ML classifier flagging it as malicious and ClamAV detecting it as a phishing trojan. The 'SE_CLIPBOARD_COMMAND_LURE' heuristic is critical, suggesting the document instructs users to paste content into a command-line context, which is a common technique for executing malware. The embedded URLs point to compromised CMS uploads and disposable hosting, further supporting a malicious phishing or downloader campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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://nomylo.ru/uplcv?utm_term=telegram+ios+for+android PDF link annotation
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138ee59bf302---nowajorokuburupafolux.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/ce45f2ffe8ec4f097a5ecd0f121dae62/34685807371.pdfIn PDF document text
    • http://futureinfashion.com/ckfinder/userfiles/files/96360998690.pdfIn PDF document text
    • http://gordostcrista.ru/userfiles/file/4738012281.pdfIn PDF document text
    • http://quartierdete.fr/uploads/fckeditor/file/45736861635.pdfIn PDF document text
    • https://optimustelecoms.com/ckfinder/userfiles/files/93166239439.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/31701757809.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/8tglkk1u7ncaup4htc8ggtu50t/44658786887.pdfIn PDF document text
    • http://hebammenglueck.de/ckfinder/userfiles/files/57885256790.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/gijifixuwo.pdfIn PDF document text
    • http://hnkingdee.cn/Files/file/202196125212.pdfIn PDF document text
    • https://thietbigas.net/media/files/buxelojewegax.pdfIn PDF document text
    • https://nordavril.com/userfiles/file/mafukalijezedo.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/situzipaliletunusepo.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-14/20210914011957769119.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/bulebexemebubowuvu.pdfIn PDF document text
    • https://congnghiepxd204.vn/upload/files/80562939566.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_off0000f3b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B0 20232 bytes
SHA-256: d88aa0f750b39e7d9bac5ccea6172e362cd7bd3e8e41e3be1f5ea53856124806
font_01_sfnt_off0001291a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014131.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14131 10560 bytes
SHA-256: 1ce0b6982cc7d446e4f4ff9c723f4b78413afbb6ecbc354b1079fba78e4720a2