Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf806384c5781522…

MALICIOUS

PDF

88.8 KB Created: 2021-09-11 17:57:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 71c0f3cee16af6ac7b37a6804d654b09 SHA-1: d0763314ca8e112501fb0877d1fab44397929d5b SHA-256: cf806384c5781522eee247a8b2c4ef9d31d124e2bd800b0900cabcda501a7994
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The file's structure and URL patterns are consistent with a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://coretry.ru/uplcv?utm_term=android+connect+to+5ghz+wifi PDF link annotation
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/4tuhgtseo4psk9s2sii0vgoi72/72196686188.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210911_174514.pdfIn PDF document text
    • https://www.edmcenter.xyz/ckfinder/userfiles/files/bibululovijepezeradewe.pdfIn PDF document text
    • http://thelifelesson.net/home/tappingchanges/public_html/dowalumniusa/ckfinder/userfiles/files/66318548562.pdfIn PDF document text
    • http://hepiran.com/cache/fck_files/file/metorelazunawodenebun.pdfIn PDF document text
    • https://impulsa.mantareys.net/uploads/plantillas/files/muzubo.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/dudipivukobanugezudol.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/rizipiletogegubetejegijum.pdfIn PDF document text
    • http://www.ih-consultant.com/ckfinder/userfiles/files/gukivuwepogike.pdfIn PDF document text
    • http://dierenwinkelindex.nl/images/uploads/libosiwividitagufebos.pdfIn PDF document text
    • http://a-aqua.fr/ressource/site-image/files/40340536789.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/mulele.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/f46e40b82c31a1b85a1391990062dbb8/popor.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/e8ba0fe757d6549f4ab4388b105cf93f/meweriwagikulomikagujo.pdfIn PDF document text
    • http://dzstock.com/Upfiles/file/nanena.pdfIn PDF document text
    • https://ckeditor.pamlskovnik.cz/ckfinder/userfiles/files/vimezog.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130ce8776fb1---fukurekufakisiribet.pdfIn PDF document text
    • http://www.ujepites.hu/userfiles/files/satixadi.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/musivolixoladupa.pdfIn PDF document text
    • http://seamacros.com/upload/file/wunelajinebudawemuxof.pdfIn PDF document text
    • http://thegioixedap.net/upload/files/kazekonixirozevasusanov.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/zafarosebenipefakanetavon.pdfIn PDF document text
    • 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_off0000f3b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B5 18968 bytes
SHA-256: 93643914ee9fb646f0b9ce4d14a67327cafff0372bd00f9a263cd63a5ae05857
font_01_sfnt_off0001257d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1257D 10640 bytes
SHA-256: 7f3388779148a9f4ad09b102dad9083d0c3826793af87bf472c1a130cf4805c1
font_02_sfnt_off00013db8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1