Malicious PDF — malware analysis report

Static analysis result for SHA-256 55af51719dcad8b7…

MALICIOUS

PDF

80.0 KB Created: 2021-09-17 09:41:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 71c80abd2feba2dbd9976723044844c7 SHA-1: 41ab84971c6bb3b14d1f1d6c9ddcabaebdd3be3b SHA-256: 55af51719dcad8b7ae02c9969900fd80531a5905ef47102128df92b2a9a4059b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, forming a link farm. The presence of embedded JavaScript and ClamAV detection as 'Pdf.Phishing.Trojan' strongly suggests malicious intent, likely to lure users to phishing sites or download further malware. The ML classifier also flagged this PDF with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=pokemon+black+patched+rom
    • http://songhakbbq.com/uploads/files/86747224301.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f63d9762e2---tetisadobaxaxubagowage.pdf
    • http://branpc.in/ckfinder/userfiles/files/gofunex.pdf
    • http://etre-belle.su/images/file/dozefidifavase.pdf
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/7c7bf17cca9ecd86661b24c0ab7eb1b6/21503300242.pdf
    • https://skinrepublic.vn/webroot/img/files/74681978802.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16141c3af04a6f---62423362089.pdf
    • https://guineaservicesproviders.com/gsp/files/65014484649.pdf
    • http://hbaoge.com/upload/files/bezaregelep.pdf
    • https://www.pirkitpadangas.lt/ckfinder/userfiles/files/kojuzinogekolagumufugeko.pdf
    • http://s2ipower.com/survey/userfiles/files/67687201808.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161313509968bd---vapexisasesima.pdf
    • http://canoto.us/Images_upload/files/51384983413.pdf
    • https://ratco-hardware.com/Ups/files/zisipa.pdf
    • http://mrcookie.tw/upload/editor/file/051759479005.pdf
    • https://hondamienbac.vn/userfiles/file/pafoban.pdf
    • http://elcolono.net/userfiles/files/tedaxareliku.pdf
    • https://www.thaiahpa.com/flash/files/xutezunamamesenuzajuritib.pdf
    • http://iccj.jp/images/uploads/fckeditor/file/59821755015.pdf
    • http://autofactory-jin.com/js/upload/files/luvowiku.pdf
    • http://ebbers-schilderwerken.nl/uploads/files/jiwokavudaxebosinuko.pdf
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161372db3a2fd5---21835127599.pdf
    • http://spielundlicht.de/content_provider/documents/files/88788058590.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/0hjpn6bi9nn53sad211g6g36qd/31445619699.pdf
    • https://xtrafitcoaching.com/www/images/files/bitafadan.pdf
    • https://himalayanthailand.com/image/upload/File/sigaz.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d261.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD261 16792 bytes
font_01_sfnt_off0000ea73.bin
5b2ac36e28a3294df1a408efece4afdcf57932e5d81f1aea04178d41149a9ebd
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA73 18252 bytes
font_02_sfnt_off000119ad.bin
00b8462110798900aefec6807bdad3bc8de8d6489e4f98f173fc1fa27febeb97
pdf-font-stream PDF embedded font (sfnt) at offset 0x119AD 10752 bytes