Malicious PDF — malware analysis report

Static analysis result for SHA-256 822808f8185ac743…

MALICIOUS

PDF

120.6 KB Created: 2021-08-10 22:57:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e94ff7fa00ca75581210d6f51ffd6ddf SHA-1: 3845db314746488aee3742043443dc72f6860976 SHA-256: 822808f8185ac7436a5c6fcaafee264bb2fcb2185be32265efae37114b8d1f27
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple domains, including compromised WordPress sites and disposable hosting, which is a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://ka-base.no/images_students/files/88231218753.pdf In PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e729b0aa35fbbee289f1fe029fce7ea1/49154661725.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/3062766d8dc861aeb2deb5a9a2d0b5b1/85281606366.pdfIn PDF document text
    • http://inncredel.com/uploads/46343260129.pdfIn PDF document text
    • https://contabil-fiscal.ro/mm/file/jafivudiwutaj.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/p88q4lamt7n11f3p02t1q7uvlf/gipekugalinibap.pdfIn PDF document text
    • https://talaa-obour.com/webmisr/uploadwebmisr/file/58528991328.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210625_9DC4C1AB8E065864.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/44d9a817ebf8abde1ce4c95952bf1e2e/gijanovagekivuxarege.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b8ffda7bf---41780058174.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/051071a891f0632e2b033cd8bd495467/xitida.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e00b355c38d---kewutebesemomox.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/29f1e029aa54de9084b7bd7521bb1acc/89319563293.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/xupajefodikawodosur.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/7dd11f83d03388b4ec3af574f5538406/pabidimoxubiputa.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/r6hj1qqneukjoc4bqe29ee9dgr/zegaxo.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/5169a6dff266ac4ce8053644df7be293/xiwakizikutoxaruvarimisu.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/pizop.pdfIn PDF document text
    • https://lesura.net/userfiles/file/15739325243.pdfIn PDF document text
    • http://centromedicoveterinarioadda.com/userfiles/files/bowenovumirepizoguri.pdfIn PDF document text
    • https://quangcaowebsite.vn/uploads/files/votidepifusekarozix.pdfIn PDF document text
    • http://laclonghotel.vn/upload/files/gusususawegakonitap.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e8baf069cdf---23784521149.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/5180668673.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=kafirun+suresi+tefsiri+k%C4%B1saPDF 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_off000175cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x175CB 18880 bytes
SHA-256: 4fd0b305f3f9c72fb11c49549aec5144ff65c9ff7f054ab452f51511306f46f1
font_01_sfnt_off0001a36a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A36A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001bb81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BB81 10272 bytes
SHA-256: 60120d48fafa11b032bb7af50bdd5c11564d9fc19bf608fd7717ae8df64914fe