Malicious PDF — malware analysis report

Static analysis result for SHA-256 21d05094fae62afe…

MALICIOUS

PDF

82.5 KB Created: 2021-09-17 04:35:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 183f0712b3df4ecd914ebc0ccad65356 SHA-1: dccd5ca9bd5823bc5f7838156fb5d9d38c037f67 SHA-256: 21d05094fae62afe650e7fb7f5815ecfe85b6f36120e3440d3d35433348cfeb6
156 Risk Score

Malware Insights

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

The PDF document contains a link farm, directing users to multiple external URLs, some of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://kemnhapkhau.com/upload/files/21555254786.pdf In PDF document text
    • http://jinruily.com/UploadFile/file/20210917085053442.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c6e9a759a525e1aa8e6f905b41590a67/94389956736.pdfIn PDF document text
    • https://virker-ikke.dk/files/96123283728.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/hcd2315k3fgam1ka8ka54o6bbe/xajibojubodi.pdfIn PDF document text
    • https://mamo-tato.ro/userfiles/file/zubeko.pdfIn PDF document text
    • http://thevisionkharj.com/userfiles/files/vokojaduzadibagosegube.pdfIn PDF document text
    • http://honderhotel.com/UploadFiles/FCKeditor/20210917080603.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/43864732463.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/nimukifunanikupabuwigoji.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/161313aa97fcca---rufoposepopej.pdfIn PDF document text
    • http://owop.challengersports.com/ckfinder/userfiles/files/budopilevamaxupotabole.pdfIn PDF document text
    • http://evrokomplekt.ru/userfiles/file/99991100251.pdfIn PDF document text
    • http://bosch-elektronarzedzia.pl/catalog/file/nusawubufodumejugenazotux.pdfIn PDF document text
    • http://wieswioska.pl/userfiles/file/nufozitisusakepepujo.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/1209077197.pdfIn PDF document text
    • https://3eyamaichi.com/upload/ckfinder_temp/files/20210908081649.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/32432453850.pdfIn PDF document text
    • http://aeusjtu.pretty-match.com/upload/files/ganev.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/65836806675.pdfIn PDF document text
    • https://groupekineconcept.com/userfiles/file/pugituk.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/vusanok.pdfIn PDF document text
    • https://channeloflove.com/ckfinder/userfiles/files/regosudokurokitemova.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/73177034964.pdfIn PDF document text
    • http://amsaneeraus.fi/userfiles/files/vafaj.pdfIn PDF document text
    • https://www.mediawerf.nl/bundles/store24backoffice/ckfinder/userfiles/files/widowatebokabibisopogis.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=thrilling+fencing+master+mod+apkPDF 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_off0000d200.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD200 21380 bytes
SHA-256: 9727e5b8a67187b6c2993ab7a2ac4b5286075e8aefd36dbb7c12f1e9748b961f
font_01_sfnt_off00010aa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA5 11124 bytes
SHA-256: 4033a17cf24c3e85aaf49d58108971560da273fd7dc200ad5955cf9e11719b19
font_02_sfnt_off00012435.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12435 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1