Malicious PDF — malware analysis report

Static analysis result for SHA-256 990874654cb8e3b5…

MALICIOUS

PDF

103.3 KB Created: 2021-08-14 12:33:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: fa23217b042b9c74e696ca9608fe07d3 SHA-1: 92c6abf0ad02c743004df143ff295a7d8e3bc80c SHA-256: 990874654cb8e3b5c1526aeb6bbb465074dfa85d9925a5401e17512a66acb656
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is unreadable, but the heuristics and numerous extracted URLs suggest a redirection scheme to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://archissimo.eu/userfiles/files/jadawatamokepunaga.pdf In PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c725c6cea4d---44668970759.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf4499ca7c---25912562475.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/zirutetevofesosovulesesuf.pdfIn PDF document text
    • https://mabuksusu.com/contents//files/12590908733.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/komedas.pdfIn PDF document text
    • http://luvnchrlysenglishtoys.com/clients/861429/File/pukikozirinorijo.pdfIn PDF document text
    • http://eltonltd.ru/sites/default/files/uploads/dupawadagawimufuveruzem.pdfIn PDF document text
    • https://edinburghpools.com/contents//files/93356894404.pdfIn PDF document text
    • http://recit-de-vie.fr/userfiles/file/gosojenopiru.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/maforofaviwavokawez.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/5e114819efc7704be1ebf8a2a16851a4/94648666357.pdfIn PDF document text
    • http://crmloccitanecr.com/campannas/file/96835134857.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160a15ed156b0e---77156790852.pdfIn PDF document text
    • http://arslanemlak.com/E/file/28631485892.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160769f932aba7---kupomudoginefirobixewub.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/rudutabiwozug.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f574a266c40---80579730018.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/60e2e3df601dc86c888b5086ae866b3d/1460708274.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/72997394694.pdfIn PDF document text
    • https://247christianity.org/fckeditor/userfiles/file/gagukabutofu1621120593.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/nutibapi.pdfIn PDF document text
    • http://bruisedreedfoundation.org/clients/4/4d/4d9d7eec3bf3a09fa0457ace138f6a4e/File/38233261777.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/lonedojufinizosesikematu.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160bb854a1091a---xidodanopevadoginumol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=basics+of+ordinary+differential+equations+pdf+for+engineering+mathematicsPDF 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_off00012b9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B9F 18280 bytes
SHA-256: d4a72172647727c9e261eff256ea7d8145b8671262e38fa887d135d77a0bbb1b
font_01_sfnt_off00015b8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000173a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173A6 11480 bytes
SHA-256: 1f41e74a161883294103d7e9feb4907695b0a351a62a2c846b21b12462d81c75