Malicious PDF — malware analysis report

Static analysis result for SHA-256 889ca22ceb7343bb…

MALICIOUS

PDF

70.4 KB Created: 2021-09-30 14:23:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9f93ac0755ddf91ef21e3e17d7ad9167 SHA-1: 747cfa1e8364ceb738d882c7f01bc915b0bd9c5e SHA-256: 889ca22ceb7343bbfb9974867d7ea37349d1a2032ae7f24e79330015ed5daf0c
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics points to a tactic of directing users to potentially harmful content.

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://krisoc.ru/uplcv?utm_term=power+rangers+2017+free+online PDF link annotation
    • http://vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/98432621528.pdfIn PDF document text
    • http://ux-school.ru/files/files/8984055267.pdfIn PDF document text
    • http://ledspectrumthai.com/ckfinder/userfiles/files/wupuwuwuzobil.pdfIn PDF document text
    • https://apgr.eu/UserFiles/file/bufapedofu.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/29298164037.pdfIn PDF document text
    • https://webaprint.be/img/file/pesozobukesov.pdfIn PDF document text
    • https://calson.garment-pro.com/ckfinder/userfiles/files/lowetokavepam.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1615595a686d0c---93158426463.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109090252113063.pdfIn PDF document text
    • http://studiofagiani.eu/userfiles/files/49948980619.pdfIn PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/fuvimul.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///bixug.pdfIn PDF document text
    • https://cvzona.lt/resources/img/files/vemobakamofo.pdfIn PDF document text
    • https://markiza-trade.ru/admin/ckfinder/userfiles/files/91697428287.pdfIn PDF document text
    • http://arucax.am/user_images/file/40220858732.pdfIn PDF document text
    • http://parikshitconstruction.com/uploads/wasunagulizopukufe.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/molenafobanogesetuliroj.pdfIn PDF document text
    • https://ultralloy.net/upload/files/wugagatulegoxumog.pdfIn PDF document text
    • https://anyimaker.com/upload/users/files/zilodod.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615591aecfd1c---99059739509.pdfIn PDF document text
    • http://www.americaninvest.net/upls/files/2827879444.pdfIn PDF document text
    • http://zgkimsteszew.pl/img/upload/files/jimaset.pdfIn PDF document text
    • https://ssvacancy.com/ckfinder/userfiles/files/84976626553.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_off0000b095.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB095 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8A7 16756 bytes
SHA-256: aeed93c33e51252e2bd97e639e81f788510d909b136d9790d03f87414af920f1
font_02_sfnt_off0000f336.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF336 10724 bytes
SHA-256: 577cc89e6f4b0184f2edc3fdb7ec4e38d50e2601d0d504919dc6cc9b8a26e5c3