Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cdf50b01cf141a8…

MALICIOUS

PDF

79.6 KB Created: 2021-09-20 22:59:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8c5bce6a2bc6389a6ddad36b794ab113 SHA-1: f6d2bd708c0cc655b462bfafb2a2b998920459de SHA-256: 1cdf50b01cf141a84d3df8ea62a28bf1616c377a47670a486c1007acc20aba34
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to various domains, many of which are associated with link farms and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, indicating the document is designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://queure.ru/uplcv?utm_term=a+hidden+life+full+movie+watch+online+free PDF link annotation
    • http://superazs.ru/images/news/file/beligow.pdfIn PDF document text
    • http://ls12368.com/userfiles/file/kosezozurevukeg.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/gitox.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613f58554beb2---13826335155.pdfIn PDF document text
    • http://purepassion.pl/userfiles/file/86050271912.pdfIn PDF document text
    • https://12shio3.com/contents/files/mevikidona.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/40765740793.pdfIn PDF document text
    • http://master-stroi76.ru/userfiles/file/55652600000.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/31581131782.pdfIn PDF document text
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/tosuzolusun.pdfIn PDF document text
    • https://carlojans.com/cms/file/zutujasuvorozuje.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/redufegowedomi.pdfIn PDF document text
    • http://moneymaker-gold.de/files/xakurafe.pdfIn PDF document text
    • http://grandfiltr.com/files/file/2202445711.pdfIn PDF document text
    • http://sattosushi.com/uploads/files/bifovewaxaran.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/sexakuxur.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/161400a4b399d3---45615575915.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/64429095684.pdfIn PDF document text
    • http://eichler-kammerer.de/86379851362.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/bepanexifefimifolelok.pdfIn PDF document text
    • http://kantipursecurity.com/userfiles/file/gemubuwasupizukor.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1614755abc1d14---11634893047.pdfIn PDF document text
    • http://bebsulmare.com/userfiles/files/59978748718.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://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_off0000cfd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFD0 10804 bytes
SHA-256: f210bc362c752c03be87006acf26abdfa8db697def1951b6217b5d57168fe9dc
font_01_sfnt_off0000e88c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE88C 19176 bytes
SHA-256: a216470059a48640f45be320a382dc432d320dcb3e60d100449baa0dbe442cb4
font_02_sfnt_off00011af1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1