Malicious PDF — malware analysis report

Static analysis result for SHA-256 99fdaed1c49a9f7f…

MALICIOUS

PDF

80.6 KB Created: 2021-07-03 20:34:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0419235f565c7929e3349f2160b1731c SHA-1: 40aeb89a9b0e456b5cc737a8399fae65b2fab10b SHA-256: 99fdaed1c49a9f7f23b8b296c9cc8021adc7edb2541fd2d682fced73b066cfc0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the structure and URL patterns are consistent with malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

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://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/bqmnam4elud61utob4djkdug6c/kijojasu.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608e5f812839d---87264495029.pdf
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/qd2l1rfocrrk3glfik39tar1qh/34350415150.pdf
    • https://aiwatopup.com/ckfinder/userfiles/files/34448202940.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac7224c37a9---lemelegenokaf.pdf
    • https://lienlacanien.com/img_pages/file/38129741935.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d08836eca6---zelobopariz.pdf
    • https://allmassage.net/upload/file/20210518212703.pdf
    • https://callalilyvn.com/upload/files/14299345686.pdf
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/26a5aa4af88f776659d0904146176fd7/kofasosexuderego.pdf
    • http://gasthaus-steinkirchen.de/img/editor/file/47077915980.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1607d554628bdb---90864189025.pdf
    • https://dewalt-naradi.cz/media/upload/editor/file/vikotaxajukomaxo.pdf
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/f8310f280200b5032a8f9bacfeb67daa/49318102294.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609bde30c5682---feseretatut.pdf
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/87l93tclbh0tglsljtjeroq1rs/68262459604.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160949d5f39a19---vitewemuxi.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/c866097e1f28c66a76b6c66c7a094414/53607219443.pdf
    • https://balaji-technology.com/userfiles/file/bonolodeda.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/52b6f7673fd48732170733d85290fdff/gozozilenudajazilipe.pdf
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/0def3272a30421518eba511eed4cfd32/69919881141.pdf
    • http://unseenadventure.com/userfiles/file/93714502763.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098a68c7f88c---vetifubasusigavugatego.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=new+dares+for+friends
    • 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_off0000c381.bin
19791a65b4d10235d64793487db1dbb1d7cfd8ca9c26ca691599f89567e6b0de
pdf-font-stream PDF embedded font (sfnt) at offset 0xC381 17044 bytes
font_01_sfnt_off0000efc5.bin
4daff10f4255c8d799c9f60e00d620f3bf73dd6c6e31d18f7752ff13c883d2c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC5 10264 bytes
font_02_sfnt_off00010706.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10706 16792 bytes
font_03_sfnt_off00011f17.bin
fd494554c7a7a2c4488382a78096c535ff133766c7221992be4f6a58596b2467
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F17 16164 bytes