Malicious PDF — malware analysis report

Static analysis result for SHA-256 c028e539bf37eb78…

MALICIOUS

PDF

83.7 KB Created: 2021-09-06 21:29:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 07d3afd08bc58ee5ff25c81e70fe5570 SHA-1: f3cf20a39248cc3035504b1317b9b6e5531988ce SHA-256: c028e539bf37eb78565b657aa0c6d266270aa8b9cde7a802702026bea92bb857
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URIs pointing to compromised WordPress sites and disposable hosting, likely intended to redirect users to malicious content or phishing pages. The presence of embedded JavaScript further suggests potential for exploitation and execution of malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=mla+8+format+pdf
    • http://4seasonstours.in/userfiles/file/wubaxunojosiw.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160829102475c2---7343446306.pdf
    • http://ngor2-3.com/file_media/file_image/file/69039435904.pdf
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/72619103513.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160adac418f125---galijarewobabik.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/b075v4iimfoil0ppl6mr4jf6kv/rotujosevewon.pdf
    • http://podhoru.cz/userfiles/file/xopaxonatovaneke.pdf
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/efmf090jhhj0ipmbiihgdscou4/jomarovibudepesaren.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161034f5ccac3a---xumemisofupapolirud.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/161258e3134ddb---60755279435.pdf
    • http://kechengchem.com/upload/files/votopeg.pdf
    • https://dptech.vn/uploads/files/tivepadapi.pdf
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/c75218259baafc049933060ca91ee8df/tevopuzizivasupem.pdf
    • http://tetobox-budapest.hu/uploads/files/dalunav.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a42213b1db---78126954891.pdf
    • http://ccsctda.com/ckfinder/userfiles/files/20210811_210317.pdf
    • https://octvads.site/js/ckfinder/userfiles/files/88819342099.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed0c0e21ed---gubewujekuzoso.pdf
    • https://grup-insaat.com/userfiles/file/13890976570.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084361a8c6a8---52217885594.pdf
    • http://driver-jazda.pl/upload/file/mebegekifepuperan.pdf
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e78423446---duwopabumaruxalexukuno.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/79e4e1915d1a53d0ed8384fd9199a95f/xomen.pdf
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/c9dae4c169n13h70u8heeuiui0/nibaborolifulaxa.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_off0000e237.bin
a52245b1775e0df2b0547364b65e947b8e8f3bae6aefb94fe00ad6986420940c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE237 10364 bytes
font_01_sfnt_off0000f9af.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9AF 16792 bytes
font_02_sfnt_off000111c1.bin
83e2a4cf58383fe178a9d65738176f5e568595c39b607102e391f618e971505e
pdf-font-stream PDF embedded font (sfnt) at offset 0x111C1 18508 bytes