Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a0e025aa4369c87…

MALICIOUS

PDF

87.0 KB Created: 2021-09-14 16:06:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1b62f7d1d15b16017649a1b6b27305a8 SHA-1: 4f3883b7a604363dbd7bf021000d07e03ed32b7d SHA-256: 3a0e025aa4369c87a2c0d509e8046bd220920a8fc126aefb704f64d6cdccc31e
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload storage and other disposable hosting sites, suggesting a link farm used for phishing or malware distribution. The presence of external URIs and the overall structure point towards a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://yoron.net/up/files/33881265671.pdf In PDF document text
    • http://www.pataniforum.com/admin/jquery/ckfinder/userfiles/files/jikomezejatawu.pdfIn PDF document text
    • https://pisangmanis.com/contents/files/59608083626.pdfIn PDF document text
    • http://danieldesignpro.com/userfiles/76898242601.pdfIn PDF document text
    • http://health-bridge.in/upload/file/69819103652.pdfIn PDF document text
    • http://skia22.ru/pic/file/domanuzilofuzugav.pdfIn PDF document text
    • http://khojedu.net/userfiles/file/radamewinu.pdfIn PDF document text
    • https://ipic.vn/userfiles/file/malodetumotaf.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16134afa71108f---29197919927.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/91243321350.pdfIn PDF document text
    • http://christopherdallo.com/file/subopepixu.pdfIn PDF document text
    • https://www.psk.com.au/application/third_party/ckfinder/userfiles/files/27611665141.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021090522314824.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/40296670135.pdfIn PDF document text
    • https://fullmagicweekend.com/ckfinder/userfiles/files/3772433427.pdfIn PDF document text
    • http://mercuresamuichaweng.com/admin/file/pazenubadoniwujelerubugik.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/69c6bbffc9308b3f9bf6661b5c592b1b/51192511265.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/77f4a84b149d087c66e9f8041558c958/33342877496.pdfIn PDF document text
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/novixolozefudewaferix.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff59985967---kevasifonuwub.pdfIn PDF document text
    • http://longthinhphat.net/uploads/files/palunajuxe.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0d09ecd6a---94044814478.pdfIn PDF document text
    • http://dayuntang.com/assets/uploads/ckedit/files/20210911083623.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=streaming+kimetsu+no+yaiba+season+1+full+episodePDF 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_off0000ebe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE8 11416 bytes
SHA-256: d1247181bd4bd27e5efc6c354dbd4e11388e4a442b94efc93da0b2b2b5a4b311
font_01_sfnt_off0001067b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1067B 18124 bytes
SHA-256: 47eac9760b0f0f56a0776020e052456ca739f243e54da1179a8515b808176eef
font_02_sfnt_off000135d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1