Malicious PDF — malware analysis report

Static analysis result for SHA-256 31d6e23ccfc9ab8b…

MALICIOUS

PDF

80.4 KB Created: 2021-09-06 02:21:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 605ac1c8e143a92df6c10ec5c7df289e SHA-1: cad3acbca4e067d8dcdc78c0e86e684b38f1c08a SHA-256: 31d6e23ccfc9ab8bb5079dff2ad083a542d2127e6b89d82cb690886abc79634a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • 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.
  • 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://mylin.in/ckeditor/ckfinder/userfiles/files/kodutatinolutovaloda.pdf
    • http://campingwithconvenience.com/files/files/kabigujobunizinaboto.pdf
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/rujirasegarisenanotaxego.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fd791a8fa20---kepagemulokiwajewa.pdf
    • http://sungwoneng.com/upfile_editor/2021/files/zatugalozirave.pdf
    • https://www.vek-bg.com/app/templates/js/ckfinder/userfiles/files/lutaxutuxit.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e360a9269d3---68618272540.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a873549fdf7---67289928404.pdf
    • http://koreaseals.com/ckfinder/userfiles/files/2116186488.pdf
    • https://aviseco.ro/userfiles/file/gudefazadevevuwof.pdf
    • http://af.ssla.ru/images/fornews/files/zebovuzelaromi.pdf
    • http://dodogs.ru/sites/default/files/file/75316496517.pdf
    • http://teraval.cz/res/file/56890651024.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612b22384b03e---12060785816.pdf
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/69957034628.pdf
    • http://kayapaliinsaat.net/file/49971172415.pdf
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/513bde08961022b98aaf4d2c8c9ddc0f/tepofiwubiletu.pdf
    • http://titadoorbinhduong.com/upload/files/relipujisinesiru.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/d31a1286051b92e1d7f1cdfd9aac0e09/fugonivigomejazexa.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f146e21eada---kepogiko.pdf
    • http://stfrancisfrankford.com/clients/9/90/9051900d87e3fdd5bc97eff612ac54c4/File/50512770079.pdf
    • https://timminsrenovations.ca/file/tgX49x5NB7daWhGL.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607be61fd0e06---41915570594.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/go1uoageqvda8l0mbk1ljmacoo/vukizidazezolurogirogi.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/531fc0ce1227767490c0b2718ee38269/23130407195.pdf
    • http://tantex.org/tantex/tantexuserfiles/file/50287148088.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=condrocitos+y+condroblastos+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_off0000d189.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD189 16792 bytes
font_01_sfnt_off0000e9a0.bin
04c5bea1a1d6d67eb945f75c9e76214281292e6ad76eaf94f4bcd66d91c37762
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9A0 10764 bytes
font_02_sfnt_off00010255.bin
9ba0327b26512bb882b09b2995406257ca688e403e71c05283c5d97c4d42ce9e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10255 19456 bytes