Malicious PDF — malware analysis report

Static analysis result for SHA-256 cca65b61d52aa23c…

MALICIOUS

PDF

76.4 KB Created: 2021-06-29 11:33:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e897d8a3e3230b0bcdd2d86a88e7d0de SHA-1: 5d04a2afb8ac6272f72c3bd58230603399d211c3 SHA-256: cca65b61d52aa23c20aaf2823f291b0c993b1b050655388671be676c60afeebd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by a machine learning classifier and ClamAV. It functions as a link farm, containing numerous URLs pointing to various websites, including those hosted on compromised WordPress installations. The presence of multiple links on disposable hosting and the use of UTM parameters suggest an attempt to manipulate search engine rankings or distribute malicious content through indirect means.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://ta-taiwan.com/app/webroot/userfiles/files/65802685834.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16081e513ecd9b---zazuwebuda.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf49dd3b4d---jebugotoxifusoteza.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/4r0lqm9jtheqaee4lsmj0eeafk/nudiwolorosinofodomad.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/0ca12b6844c8a0a01aadf09f755461f1/dimufogivigexisim.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607202892bf3b---nonakawajigapowipakab.pdf
    • http://harissarantis.com/userfiles/files/fupinirimiwosofud.pdf
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4a9484b3a---banufanoderunuga.pdf
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608651d3cf6d6---bugojiwaname.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b1d4a9a8990---36034573653.pdf
    • http://lawrence-spruill.com/clients/42275/File/zuwadaxowonoliwajiz.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cb9b7a895---92464130645.pdf
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075f7d595512---85122695884.pdf
    • http://fecoil.com/userfiles/file/gopevijigutowobogeraf.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160762ff877ab1---jatinewap.pdf
    • http://stavebnevyrobky.sk/www/upload/files/kofugotegezuluba.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/i2ts4mhj7m9td1d7ica6qdk4ee/37215435117.pdf
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa051a99592---famopopuwemekiniwujul.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1609473424dba1---48110569118.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/f84db04af1599afe145a10af178108f1/wubegimaz.pdf
    • http://3suntech.com/UploadFile/file/20210623041531581.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=climax+story+example
    • 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_off0000c748.bin
395dc006b41975d2ca69420914973ac761db894689128f1105190e3e2fbe6a94
pdf-font-stream PDF embedded font (sfnt) at offset 0xC748 17552 bytes
font_01_sfnt_off0000f591.bin
5e895987a1530a95f45ea70dcfe8e6e41d7e0e6e4e375c394d777c56ced9c7be
pdf-font-stream PDF embedded font (sfnt) at offset 0xF591 10556 bytes
font_02_sfnt_off00010db6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB6 16792 bytes