Malicious PDF — malware analysis report

Static analysis result for SHA-256 b564de5e4cb429f2…

MALICIOUS

PDF

80.6 KB Created: 2021-07-02 09:12:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40f65fe4cabdf75d6dfa7bb1da94defc SHA-1: fe41d02aeb94ff66e15418f89febeffa9f3ad8f4 SHA-256: b564de5e4cb429f28dc9988542a2f598a297fc2ca96a073f45c479c4a7d2add0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, which in turn host other PDF files. This structure suggests a link farm designed to distribute malicious content, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly indicate malicious intent, and the presence of embedded URLs further supports this. No scripts were extracted, but the overall pattern points to a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607fea322cac9---46702686969.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160be4f140342a---13227163469.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bfaec2c40e2---nadegatubavorovafupakuf.pdf
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/avibm63a54h4lfdcnq6pscmo3u/75245197967.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a92987285f9---1095668599.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb3578e169---vebosulexemu.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/f4818be331ab8de7f9be72f9f42dab01/dubukajibave.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e90eb95af---dosunari.pdf
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16081dc7865c7d---81654903644.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/nqs0vcnal49nhonev9p1dtrfq7/gaxebipapadupugasajox.pdf
    • http://tweedehandswikkelaar.nl/app/webroot/files/userfiles/files/zutumixi.pdf
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/bapvfam1n9tvo6b93csb5nlt0b/mumolekakuv.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160750662c6ed6---xobelemobanoju.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce6d131cbf3---20944677001.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074215a9e7db---mefupubuwe.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16089a320b6fcc---libegijajodevex.pdf
    • http://best-infosystems.com/userfiles/file/23204622912.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/639fe6b423e5cae77ba5d79df8ead87f/77987414997.pdf
    • http://rowerowaszkola.pl/imgturysta/files/dukisulagelugajeda.pdf
    • http://attlas.center/userfiles/file/27245022749.pdf
    • http://klusjesindex.nl/images/uploads/44469819502.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070cec80ad4c---muxazazijunidesizurakon.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/cqnupvnkt5pf8c77072u8e594j/83828914124.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=no+time+to+die+piano
    • 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_off0000d8ba.bin
a7682cff884c43c7c564fb765243dbfa712f2635d769fa369b16637cb7617abb
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BA 17604 bytes
font_01_sfnt_off0001076f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1076F 16792 bytes
font_02_sfnt_off00011f86.bin
c9ebdafc5f64b6c7f71b9c781d2cbb38bb99256045ba922463b481ffade15d15
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F86 10216 bytes