Malicious PDF — malware analysis report

Static analysis result for SHA-256 4800dc887bd5b2ae…

MALICIOUS

PDF

81.3 KB Created: 2021-10-05 05:48:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: c4a777c04ea15968daad859829660d39 SHA-1: 278e64385142fd6a6307309c3d9b95751b9cc235 SHA-256: 4800dc887bd5b2aea26b86830d9e261fcf594dcba078d61dd3943b5c3757111e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these external links, which are characteristic of phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://krisoc.ru/uplcv?utm_term=abstract+to+concrete PDF link annotation
    • https://songod.vn/uploads/image/files/39392902364.pdfIn PDF document text
    • http://gramercy-grand.ru/files/file/finate.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/cmormlhd4p8brcb0ql0tk2q18q/pivaluniti.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/62942861026.pdfIn PDF document text
    • http://kielcenoca.pl/files/file/gunajatasoxuponavefi.pdfIn PDF document text
    • http://bhttourist.com/upload/fckimagesfile/dubuzozukoxemagiseluw.pdfIn PDF document text
    • http://hotspot-usa.com/js/upload/files/8979964658.pdfIn PDF document text
    • http://sms-dk.com/FileData/ckfinder/files/20210916_0BA0164596AF5F8B.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/leredewilodixotarek.pdfIn PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/92744827909.pdfIn PDF document text
    • http://sasolution.kr/userfiles/file/pekomozilupazepafolafitim.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/13758799632.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210906163097033869.pdfIn PDF document text
    • https://mu3yc792xh-rl1.com/contents/files/56210809694.pdfIn PDF document text
    • http://hnyinfeng.com/d/files/xowufimozefovebumanopaxan.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/94389540677.pdfIn PDF document text
    • http://villkasz.hu/editor_up/45171663694.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/dolufikarapamonodaxujipu.pdfIn PDF document text
    • http://megaprestige.ru/uploads/files/13299765082.pdfIn PDF document text
    • http://montoaneli.com/ckfinder/files/8349030920.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1615429b8b99e6---waxaguw.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/f4ef6f0482d54fe07ea0af0e7a1d7cdd/vulopulobuvixili.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD772 10208 bytes
SHA-256: b911a4eb2f56f848964d0713ad6441dd1708748f8059d9b99b0363e658be6f0d
font_01_sfnt_off0000ee92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE92 18976 bytes
SHA-256: 64e8b3ca703d43347ae37434f2de524e6d805e6fdf3fd83cf183d0c2d0816c23
font_02_sfnt_off0001200e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1200E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1