Malicious PDF — malware analysis report

Static analysis result for SHA-256 50acd6b0776519e9…

MALICIOUS

PDF

75.5 KB Created: 2021-09-07 14:12:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 558d7ddd598d57adb6b757239239866a SHA-1: f067d9924fc3ea9e2a699d57ad7d37648f377a6a SHA-256: 50acd6b0776519e9c8c6795251d447cc7b37ff24139f5c16f0cdcd347100ad72
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and compromised CMS upload links indicates an attempt to leverage external resources for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://oniceh.ru/uplcv?utm_term=worksheet+for+class+1+english+pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd589b261f0---fogowubifa.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161337e7dc1de6---80648631741.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/t74cnocmkmchlsj8917gku0ouc/52795452340.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/539b481d8b766fd81f6f580914ff9191/juzipewawipuvi.pdf
    • http://4x4autok.hu/userfiles/files/zotosaxedukej.pdf
    • http://www.aadhar-interior.com/userfiles/file/reronaregesofox.pdf
    • http://retroldn.com/userfiles/file/jijuzavibilatepeb.pdf
    • http://shiraz.sk/ckfinder/userfiles/files/wuwixo.pdf
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/ab67e1dc47179d39b12e041d267f21c3/26255166508.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7e429dff3---jodakekixof.pdf
    • http://winecellarkeeper.com/ckfinder/userfiles/files/xusozuvu.pdf
    • http://tvoirostov.ru/ckfinder/userfiles/files/wopaxifevizomepulitazivun.pdf
    • http://hotstamping.pl/files/file/rexubobasodurarapafe.pdf
    • http://alpanelektrik.com/depo/sayfaresim/file/nukodofizibuwigisu.pdf
    • http://brmxn.com/userfiles/file/20210516084748_ek1voa.pdf
    • http://h-st.nl/bestanden/files/fofofujulajizivelu.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/041c2990d4e853cc97864d260f982684/3831161142.pdf
    • http://hk-keber.de/images/file/13485324515.pdf
    • https://miet.hu/kepek/44022790791.pdf
    • http://morgancountyoh.com/userimages/lalujumudiwozizofozawaj.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16102d21b47ecf---20805873079.pdf
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/bujofakowerixegoxobukog.pdf
    • https://eliteplacementagency.com/uploads/files/64929836256.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c16f.bin
849e1bbc8d5acf7c21b5cefe05f0a2bcc2b8f06339a4832df28d4cfab7595374
pdf-font-stream PDF embedded font (sfnt) at offset 0xC16F 17756 bytes
font_01_sfnt_off0000ee77.bin
04358fe3703bd4293afac646e2cde649c058a1485bf4a048747416419bbc4e99
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE77 11036 bytes
font_02_sfnt_off000107fa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x107FA 16792 bytes