Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf5fe91881a0c2c7…

MALICIOUS

PDF

71.1 KB Created: 2021-09-30 10:01:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f9beec93ba5045af07c95019943009f8 SHA-1: 738eca65448ba1f0ac2c6e818e3841ee32f9935b SHA-256: cf5fe91881a0c2c7c290719f6dbe449e367536d96b79787164ce5fe9108dc4ac
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many hosted on compromised CMS upload directories or disposable domains, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and link farms points towards an attempt to exploit user trust through indirect redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://pradakshinam.com/fck_uploads/file/xutezazamabobow.pdf In PDF document text
    • http://chipgene.com/image/files/20210930_090050.pdfIn PDF document text
    • http://ztracenaexistence.cz/files/content/file/mogorejizixagirusikovo.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/cf979f53e837516b375384345d487b38/68488684832.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/91437686329.pdfIn PDF document text
    • https://hkki.org/userfiles/files/72808504717.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/99399048238.pdfIn PDF document text
    • https://greenlakecruises.com/ckfinder/userfiles/files/83594073241.pdfIn PDF document text
    • https://livermore.com/wysiwygfiles/file/45278307527.pdfIn PDF document text
    • http://uptownchantilly.com/uploads/files/pizuwokonilemojeniw.pdfIn PDF document text
    • https://ceylanotel.com/firma/files/mipixoxiritukimib.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/82139076911.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/161514dbba3f6e---72653735630.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/82718991535.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///notojobiki.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/61770635202.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/dalevux.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/luzimakufaxikaluje.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/fabodofunesifazawazarak.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150809829151---bugelulowakuxova.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/68ccab0c55eff0ff0e882325e3032fe7/89638208770.pdfIn PDF document text
    • https://pezenasenchantee.fr/userfiles/file/guxolujibawelenomobez.pdfIn PDF document text
    • http://benly-carson.com/product/files/96570500778.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/85397736479.pdfIn PDF document text
    • https://sarna-zapiekanki.pl/ckfinder/userfiles/files/pobisiwavutukesunuferogod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=free+tube+app+androidPDF 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_off0000b4a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ccbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCBD 10388 bytes
SHA-256: 065d9fe824f9ce860412a5cbe73d5e50ea0586072de0b88474b57ca19cbd78e5
font_02_sfnt_off0000e40d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40D 16676 bytes
SHA-256: 15f6c7e5161a299c7684cd231b0355a3ae7bd41b83d1458d773eab9a5808c972