Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a6a5e8b5ca55d4d…

MALICIOUS

PDF

93.7 KB Created: 2021-09-19 03:19:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b986941ab42cbd212d8d7539f27d2687 SHA-1: 2d819cdac68b6b592c31c7d84af8eaa971d6d280 SHA-256: 5a6a5e8b5ca55d4d96a1524053883ce985a1154e90e0af968882e408f9949f06
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing or trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests the document's purpose is to redirect users to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cuacuonbinhduong.com/upload/files/jumix.pdf In PDF document text
    • http://silverspringabw.com/uploads/files/pogedavoxixudepujamobaku.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/05db3f0281edbd95579584e75cbf5532/takizepojuwoxibibilafide.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/nokazuza.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea03a83df0---xididopufo.pdfIn PDF document text
    • http://jumpinfit.it/userfiles/files/kamepememetugam.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1613fab9d72b9c---tiwusabizekesevalevujexon.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/30469132952.pdfIn PDF document text
    • https://palezieux.com/ckfinder/userfiles/files/23854500993.pdfIn PDF document text
    • http://www.huntsvillepr.com/files/files/76449294225.pdfIn PDF document text
    • https://majubesar.net/contents/files/wimowezalefubama.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/ninu92p3tgv9shibiekn2duqlm/24143360684.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/kifumuwuvukak.pdfIn PDF document text
    • http://hzdsbg.com/uploadfile/1631168502.pdfIn PDF document text
    • http://105chers.netsociality.com/upload/files/39535760455.pdfIn PDF document text
    • http://phuwangnam.com/user_file/file/37819042249.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/19063122230.pdfIn PDF document text
    • http://domingo.hu/ckfinder/userfiles/files/55207291876.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/jogumepukapumid.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/nomitud.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/files/files/xupiwitewod.pdfIn PDF document text
    • http://xn--oy2b9bv81anouola.com/upload/file/202109140914061774.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=games+like+diablo+3+2021PDF 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_off00010847.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10847 18288 bytes
SHA-256: d031bc731f462017d1d90539adbda623c284dc44d900f34c196f502275a02153
font_01_sfnt_off000137f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137F2 10844 bytes
SHA-256: aa295162e5cd0c7fda68e9fe5ac3cf6d83a8af10ea3aef5782c16d4ed508a9ad
font_02_sfnt_off00015105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15105 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1