Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc8f60a4843c1d3f…

MALICIOUS

PDF

88.0 KB Created: 2021-07-21 01:02:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b8b66d31738fd3f7dec6545d91432a30 SHA-1: b8543cd87353caaef566c4905cfaa20980a761ae SHA-256: fc8f60a4843c1d3f3ec8cca932099bbd6c459de0dffd6e6688d455cd09ef70ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to other PDF files hosted on various domains, many of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the structure suggests a link farm designed to obscure the ultimate destination or to manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://vmkmsz.hu/userfiles/file/44015075904.pdf
    • http://eurolocal.info/sites/default/files/images/file/korebusefazivoma.pdf
    • https://amatnieks.com/pictures/image/dotepakanuv.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b623ddc90ec---taxeripukiv.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160867a5f5a32a---desuru.pdf
    • http://beastyenergy.com/userfiles/file/maxopokixifenokuf.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083023d9218a---vanisuxukedetifozutejawi.pdf
    • http://barcelonasixtytwo.com/userfiles/file/runazirunaleparidozo.pdf
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/2b17d5c083fc816a14618817034fd219/39674580144.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a17e36887---85242729429.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093def4d0044---50832758933.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b1035050aaf---53701709254.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5af764efc---27728608312.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af9bed4b5c6---funilemi.pdf
    • http://ibtaker.ps/userfiles/file/73285687119.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/73843d3359cd2a7e6618dd837305983f/35136981906.pdf
    • https://ikincielinmak.com/upload/ckfinder/files/84247239889.pdf
    • http://tantex.org/tantex/tantexuserfiles/file/rakogoxuxup.pdf
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/bff7f1d7186e2d511b1a511d5b83d079/bazufizoju.pdf
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/ibfohqot7l3n9vdaqp2sgudcs1/82141485534.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2be0c8f87e---kijune.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=difference+between+hashmap+and+treemap
    • 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_off0000f358.bin
fbb0b2fad1413cba57aad93b97104f311a6425d1daaeac111e12c53ebfd1eb3e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF358 10948 bytes
font_01_sfnt_off00010c66.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C66 16792 bytes
font_02_sfnt_off00012478.bin
f41e4976b7ab3cce006d5b65008ed532cb81940ce1a6cc1861cba6220267cea4
pdf-font-stream PDF embedded font (sfnt) at offset 0x12478 17568 bytes