Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cfbd6d858b64092…

MALICIOUS

PDF

101.3 KB Created: 2021-09-01 19:15:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 566d7ff07b92c178dbcceea11d9e2383 SHA-1: 47aa07ed61432ffeb01399a31f610b78e6500b30 SHA-256: 1cfbd6d858b640924f763c06af5fd6d1ea4f83817f3dfb2628f15a9b88cdaae1
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or SEO poisoning. No scripts were extracted, and the document body was unreadable, limiting the analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1928540f98e59754b884740e6514fb8c/88283588042.pdf
    • http://sushibelovo.ru/files/70015312849.pdf
    • http://tokstar.com/_UploadFile/Images/file/76404054081.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161057e305f27c---siboninuxovo.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16070418055204---derabij.pdf
    • http://permianhighschool1970.com/clients/e/ef/efee9fcbc667252fc4b649c8163d3733/File/67549748305.pdf
    • http://rainternacional.com/userfiles/file/vowebajimulidival.pdf
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/c46m8a6o6bcn830lia5vfl4j5c/wetelopavi.pdf
    • https://alves.bg/ckfinder/userfiles/files/77930123101.pdf
    • http://mwflower.com/upimagesfile///xekizajozigubuxogelakeso.pdf
    • http://rustproofingottawa.com/userfiles/file/63650253074.pdf
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a07bb89ee61---sagezozomof.pdf
    • https://fotoprint.lv/downloads/file/71019617024.pdf
    • http://xn--o79av69abka850ab6c.com/upload/file/202105281348090733.pdf
    • https://aduanaldelvalle.com/userfiles/file/zokibabojonisopoturovu.pdf
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/db7c9352f971aee1b919b0c18cec7598/wilojun.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/161101ce185bf6---kuvubelijitowapon.pdf
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/nekuwibe.pdf
    • http://conniecorsentino.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tekom.pdf
    • https://flyingfish-stay.com/userfiles/file/53040596206.pdf
    • http://akcjonariusz.com/UserFiles/file/32262576102.pdf
    • https://ckmandarin.com/uploads/66931381562.pdf
    • https://arch.ua/ckfinder/userfiles/files/tesuxibasifekuneto.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=crazy+future+technology
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/82374f5687a308766ac9fdbb1008b96b/duzugokilogaxu.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_off00012667.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12667 16792 bytes
font_01_sfnt_off00013e7e.bin
c3839987d133e1897e8505725e426de03cdd557561c2b7c11cd6c88b3561cc3f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E7E 10660 bytes
font_02_sfnt_off000156fd.bin
5757abe17e55865cfb7b9a7ded49c3c5dc584c252b7312228272253d0e08e6ca
pdf-font-stream PDF embedded font (sfnt) at offset 0x156FD 17936 bytes