Malicious PDF — malware analysis report

Static analysis result for SHA-256 28928add4116d172…

MALICIOUS

PDF

75.6 KB Created: 2021-09-08 19:00:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: cbec872e9e1fc9bd14935b468c9988e4 SHA-1: 60f91e6035c8e8e984f3a955302b87ed2f27abec SHA-256: 28928add4116d172a0daea715266e057f04a04eb83db52b604cb93b8585aaa38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and does not provide clear textual lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://vodova51-53.cz/files/20181907142.pdf In PDF document text
    • http://kuresi-kaitori.com/upload/content_pic/files/19455945244.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16136c4828666c---93657953465.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/96569642300.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1612f54b4843c5---46461633857.pdfIn PDF document text
    • http://intertexmedical.com/userfiles/files/birazuporovipajunus.pdfIn PDF document text
    • https://alaskaproauto.net/nbloom/fckuploads/file/33330590633.pdfIn PDF document text
    • http://sun-tes.ru/files/file/74257767755.pdfIn PDF document text
    • https://thucphamtruongxanh.com/Upload/files/tinepumokajetonikeroxirep.pdfIn PDF document text
    • https://pasarant0g3l-turbo-h1t.com/contents/files/numufajixijedinuruvazuxov.pdfIn PDF document text
    • https://parkettworld.com/upload/files/forewokuna.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/65837517430.pdfIn PDF document text
    • https://casaalu.com/luutru/files/dinidorulefajotivogusexi.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/6763952994.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613261500535f---vavabekuwaxujugaburib.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/161363c6249402---pulet.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/lcbjao5a71ape1rp4t2qt1m5s5/lixifaxevolajuzemunu.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/zavibabasozazuxijinakiwo.pdfIn PDF document text
    • http://spharma.ua/files/file/maxobe.pdfIn PDF document text
    • http://www.hgekc.com/media/userfiles/file/86605959549.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/sonobapefopo.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/vivebuwamuxavegevar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=cwic+training+manualPDF 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_off0000c484.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC484 10372 bytes
SHA-256: 65d7aa9fc152404c146d936e42727dbbc6b9febd491a7dbf26131c049410b22a
font_01_sfnt_off0000dc03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC03 17752 bytes
SHA-256: 2874c7be1340ffd6bc4c5ade5b133ddf12afbb63247914280f40842ccbfeb0b5
font_02_sfnt_off0001092c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1092C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1