Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfa4a92f21f0673e…

MALICIOUS

PDF

68.9 KB Created: 2021-09-26 22:53:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1cc887188a2753f2db6cdb4dafd88e04 SHA-1: b081035f6a7446c0976b01db8c7179aa5f144a99 SHA-256: cfa4a92f21f0673e3afa1ed359be1e2b13510c88f855b673c3ebb3aaf5ff9f19
156 Risk Score

Malware Insights

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

The PDF file contains a link farm directing users to multiple external URLs, with several hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The primary attack pattern observed is the use of a malicious document as an attachment to lure users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 6

  • 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.
  • 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://bunianco.com/other_files/File/vidixawadupomuwabapex.pdf
    • https://kaparatt.com/images/File/89029254513.pdf
    • http://heryeryesil.com/resimlerfiles/varuwukugal.pdf
    • http://lpkgoodframeupvc.com/userfiles/files/pazedimoguwatesopajumed.pdf
    • http://dorisemitchell.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gubunovunemagasen.pdf
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c98e3c5f4b---33643066796.pdf
    • http://struttur-arch.it/userfiles/files/72509551462.pdf
    • https://nepalfinepashmina.com/userfiles/file/zutov.pdf
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/merubefepawelawuxerakonuj.pdf
    • http://lynhuagiasi.com/Images_upload/files/74699904942.pdf
    • http://alompar.hu/uploads/content_files/files/xufulameregedimasowanoto.pdf
    • http://tcyy88.com/userfiles/file/2021092215465273499.pdf
    • http://debschoen.com/userfiles/file/37278380845.pdf
    • https://anukulagrotech.com/ci/userfiles/files/kizikogabukaranajapodogo.pdf
    • http://registermycompany.in/admin/userfiles/file/sipopileloverofada.pdf
    • http://tfh-filter.hu/_user/file/ruvaxajufawezaxidatexubo.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358fbd8ce24---20726186777.pdf
    • http://24cvety.ru/upload/files/vozubiru.pdf
    • http://dgkno.cn/upload/78713781951.pdf
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/87005375326.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f58a8d5966---fukexon.pdf
    • http://kronikarp.pl/ckfinder/userfiles/files/47529645010.pdf
    • http://chnli.tw/CKEdit/upload/files/vixakevefulef.pdf
    • http://badaranquehablar.com/userfiles/files/vilolajofizev.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=medieval+2+money+cheat
    • 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_off0000aef0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAEF0 16792 bytes
font_01_sfnt_off0000c707.bin
cf80ae8860c6dddc26170de7e8b5b8c0912db9cc6a4175882b9c97586f252c82
pdf-font-stream PDF embedded font (sfnt) at offset 0xC707 10660 bytes
font_02_sfnt_off0000df49.bin
85dcf759198b50935696ad4a73e6a144ce7520ed9a0f4d40d4854dbfd6c291cb
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF49 14948 bytes