Malicious PDF — malware analysis report

Static analysis result for SHA-256 6efaefacea999f42…

MALICIOUS

PDF

95.7 KB Created: 2021-06-28 12:58:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 863ed8ffd1870baa63969347934eed4f SHA-1: 9f398e609f66cf3c37e9356fe47ce044c5f4dc4f SHA-256: 6efaefacea999f427327a6c905e9aa63790f911f84dbd5ba9308ee64a88efb90
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with multiple URLs pointing to compromised WordPress upload directories and disposable hosting. The embedded URLs suggest an attempt to redirect users to malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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://study-go.info/wp-content/plugins/super-forms/uploads/php/files/17b43cc84e3fbdf36cbababc3058d39f/56166345424.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16096f1f9f24d4---29854716543.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/110e8779f4cb8afc7910b323c3d3ebcd/tekikipiga.pdf
    • https://geneolock.com/locktactyuma/userfiles/file/fikifutanugijegajibofiwi.pdf
    • https://electrabicycles.pl/app/webroot/uploads/file/16201904952109.pdf
    • http://geostudio.eu/userfiles/files/54535914894.pdf
    • https://limblength-sldf.com/userfiles/file/taduganowij.pdf
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/406c4d2043da4beb97ea7abc437ea604/97487627798.pdf
    • http://bbfederico2.net/userfiles/file/62539483460.pdf
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/h3bicvupcam0ao04ks9oe5kb76/diduronuwojaxavavori.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b8f8a9677cf---38819837158.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/afdaf82e2b57811f8ebcc213a6c58470/14008127525.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6b17787d0---82138985926.pdf
    • http://gayaarchi.com/userfiles/file/20210627052034.pdf
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/c15d21e24c1f22eefb962497eb61592b/zewulazelasoluw.pdf
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/oetl7r084mq2du237d0paimuvu/nesowukevufuperebagel.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/65b67e04495553305067e170d3c0ed1f/45502285231.pdf
    • http://greece-ex.com/images/blog//file/wegedotiv.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160769d42119ea---9221925563.pdf
    • https://baxsporthorses.com/userfiles/file/1501608950.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c89277dee33---zoxiruderowesuveganiwezo.pdf
    • https://heritagecambodiatravel.com/userfiles/file/7093350427.pdf
    • http://taiwanquinoafamily.com/shopadmin/upload/files/rowidupipum.pdf
    • https://eqonetech.com/upload/userfiles/files/pegamotewowewufutoma.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=recon+expert+is+coming+back
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B8 16792 bytes
font_01_sfnt_off00010fcf.bin
de5b1172aac2745384048110ba241334ed5bea9f76b49ea96ab509931868fd5f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCF 11052 bytes
font_02_sfnt_off00012960.bin
bd8cabab09716fada74ebfc37b5861ae0b4669e22af1f6250164bfd16ad5f5f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x12960 18036 bytes
font_03_sfnt_off00015890.bin
6852b475b3c03bb00894d1a4cf8e932c0d99446febf13fdce318669c029ad4ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x15890 16596 bytes