Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6dc4836c698cd06…

MALICIOUS

PDF

79.7 KB Created: 2021-06-11 04:10:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0009b8c9475c78c749d493048e2e0c40 SHA-1: 4c85b3f3d12613ef5e48f50d14e658ae77e5164b SHA-256: a6dc4836c698cd0618b90106a1b6726afcc2dba3e4ecc68780b2dabb20122e00
164 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous URLs pointing to compromised WordPress sites and disposable hosting suggests a link farm designed to redirect users to malicious content. The document body, though partially corrupted, contains phrases related to free downloads, aligning with a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=dulha+dulhan+book+pdf+free+download
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e99e046707---4093854325.pdf
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/bbb2c0e0757af3309c0de4780ffb9237/58635454485.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608a197d0d761---zebirekuxu.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16083e8ce5cb2d---28731422479.pdf
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608012c70e05d---lefunuzotizijorevegir.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/g01flikqv328p68qcq3qrj9oi6/gilejifabibo.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b203eff3b---76433767383.pdf
    • http://alexanderkanevskyartgallery.com/clientMedia/file/venugododo.pdf
    • http://sterkrade.net/ckfinder/userfiles/files/fijajisaboku.pdf
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/049a0833ee424bd999f4d798f1406a22/73392547113.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160793dc6d726b---16968357091.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160886ce364748---nokofuwut.pdf
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/45bab0a02806c124d6124544c418ef02/sudaxokeniriv.pdf
    • http://montaze.org/democms/userfiles/file/lojuki.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://fedorahosted.org/lohit
    • 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://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3a7.bin
412c89ec425030372ab101d9a099ee9c2db0fb227def08dce250cac1287ced44
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A7 5248 bytes
font_01_sfnt_off0000e589.bin
28fd901fcf30b8f6ac0e4849ac5f0ec6f543d9efc879418f2984c286a7e69628
pdf-font-stream PDF embedded font (sfnt) at offset 0xE589 10256 bytes
font_02_sfnt_off000108c5.bin
000d88e99c3127230c7f769a38c563a804bae54a2e6af43569e1edb98e99c5fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x108C5 16956 bytes
font_03_sfnt_off0001212d.bin
117061b7cb5870191a33a342893b9baa4946d40b3be57b8f522400b5290cc425
pdf-font-stream PDF embedded font (sfnt) at offset 0x1212D 3820 bytes