Malicious PDF — malware analysis report

Static analysis result for SHA-256 a341504b21be5c6d…

MALICIOUS

PDF

81.6 KB Created: 2021-09-18 06:53:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 44c694c77f2d9447a87bd6960d7fee53 SHA-1: aa96e9a284b1cd66c90204e496e0d3fab16285ea SHA-256: a341504b21be5c6d59cabcaffc2f45b4dbe1ed3017a579db6f68dcc7a7f8e7ae
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and a link farm heuristic confirms the attack pattern.

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://baocaosuhoatoc.com/luutru/files/kegomuwuzarim.pdf In PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161395abebc3a3---61234960595.pdfIn PDF document text
    • https://manage3.realtourvision.com/rtv/ckfinder/userfiles/images/files/vadiloba.pdfIn PDF document text
    • http://southerncross-ex.com/images/blog/file/medijirulojejesuzu.pdfIn PDF document text
    • http://angelofthewinds.org/ckfinder/userfiles/files/45936598400.pdfIn PDF document text
    • http://tlumacz-bialystok.pl/pliki/file/16320822517.pdfIn PDF document text
    • https://tectrongim.com/uploads/files/80441600660.pdfIn PDF document text
    • http://stnicholasway.com/userfiles/file/86429795203.pdfIn PDF document text
    • https://produktybhp.pl/pliki_user/File/kasaf.pdfIn PDF document text
    • http://autoservizimensi.it/images/fck/file/pudujo.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/6175150879.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/5270979546.pdfIn PDF document text
    • https://cmottaviproductive.it/uploads/file/61052124541.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140846bc252b---64934583433.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/122235273527.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/75694731996.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/bitamuvagetowipiwigoban.pdfIn PDF document text
    • https://chupwo.com/editor_upload/file/40449529492.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/64212053372.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613f65f7d4bd0---20967254592.pdfIn PDF document text
    • http://gekon.net/userfiles/file/rexujafelaniwu.pdfIn PDF document text
    • https://hanurichurch.org/ckfinder/userfiles/files/17567405264.pdfIn PDF document text
    • http://mrs724.ir/basefile/drtiketcom/files/51685594194.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/gokosaramejo.pdfIn PDF document text
    • https://strategie-forex.com/ckfinder/userfiles/files/bewojewotitudojulinasoga.pdfIn PDF document text
    • http://banner-ever.com/ckImg/files/26324487935.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=richest+man+in+babylon+free+book+downloadPDF 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_off0000d75d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD75D 11216 bytes
SHA-256: 2a4f598ae030b9d8e0ed8ff2966349cd26334e30e057cdbb7dd5802d8c28780a
font_01_sfnt_off0000f181.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF181 17808 bytes
SHA-256: 42231c4cb97712bc7817cb81e716df3e5eb877970faae27035d7097e395f02fd
font_02_sfnt_off00012010.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12010 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1