Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4efc85272553436…

MALICIOUS

PDF

80.9 KB Created: 2021-08-11 02:48:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 51bc539b3998ab95592670c6ad37891b SHA-1: 883628e632b397166e9f31e67c2c8e1c39b37c29 SHA-256: c4efc85272553436d695ba70660f3433f3817cb71fc498121d8710bba4bacbbd
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites and other disposable hosting, likely to distribute further malware or phishing content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/bbf4a300316713e6be50a01e73d8c33d/guruxajovizazejas.pdf In PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/2r406m88k9oscennsmet85h18h/muxafuwokes.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/mitapikara.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/86756558679.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/8ec44b492dd95da1feb0a200481890e6/28801968059.pdfIn PDF document text
    • http://ewhamd.net/upFiles/ckeditor/files/95654779406.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607718d1ed6af---84577794986.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///wopagasixivopapo.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/70485044158.pdfIn PDF document text
    • http://stensoproject.com/userfiles/files/81577554932.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609abcf500e9e---26218433800.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/domejetor.pdfIn PDF document text
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/97223143586.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/66483921137.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/37332cfca1a3dd19e1f7b3a043d93d73/bisiragimuzo.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/4b31efc291bd5f95e4fdba34f92e22f5/33868510810.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/xekipodabenalimerixiba.pdfIn PDF document text
    • http://ccsl.asia/files/47337241966.pdfIn PDF document text
    • http://ovodatar.hu/userfiles/file/17939865176.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/71693203286.pdfIn PDF document text
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/sozikuboferepakeza.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/zituze.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/2e4595484338e5723d54e4e7f0f3340c/muluxe.pdfIn PDF document text
    • http://woodbridgeabw.com/uploads/files/31225249296.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/3dc2pk7p057fe532l8ql4e4i76/41888176346.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=punctuation+marks+test+with+answers+pdfPDF 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_off0000d854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD854 11120 bytes
SHA-256: 67dd50ebd68c132a9fa2cbafc0ecc78975fe5a48aa9400aae0551e928337d1fa
font_01_sfnt_off0000f229.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF229 16512 bytes
SHA-256: 62b45f2373ae937e14fad350907b3201706f9f2da55f19332564f0b0411060ae
font_02_sfnt_off00011cba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1