Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e15c39231c3285a…

MALICIOUS

PDF

82.7 KB Created: 2021-09-14 14:06:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a6903ed9faf763138cd3bfe0ea7af89e SHA-1: 3a089c3a9c839755c9b194fb0b43d8ac4ba063f3 SHA-256: 9e15c39231c3285a927fe340d5341c5ef01226d84ffd62f1e402998118bb6770
184 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 or disposable hosting. Heuristics indicate a link farm designed to impersonate cloud services, suggesting a phishing or malware distribution lure. The ClamAV detection and ML classifier strongly indicate malicious intent, likely involving the execution of embedded scripts to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 8

  • 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.
  • Cloud document impersonation lure medium SE_CLOUD_DOC_LURE
    Document impersonates a cloud file-sharing service such as SharePoint, OneDrive, Google Drive, Dropbox, Box, or Microsoft 365 and asks the user to open, verify, or access a shared document
  • 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://www.bankkartya.hu/js/ckfinder/userfiles/files/pidixijawizi.pdf In PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/nubukerozin.pdfIn PDF document text
    • http://conelser.hu/fck_uploads/file/39604113796.pdfIn PDF document text
    • http://brucemayrockinstitute.com/assets/ckfinder/core/connector/php/uploads/files/sinixupubenetator.pdfIn PDF document text
    • https://betenagro.com/sites/default/files/file/75155044969.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/79719466741.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/fogibuwu.pdfIn PDF document text
    • https://notarbrazda.cz/userfiles/file/In PDF document text
    • http://www.binghan.my/userfiles/file/82598141221.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/49547121819.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/bedawijevixunodimofa.pdfIn PDF document text
    • http://eska-lift.ru/userfiles/file/61755769085.pdfIn PDF document text
    • https://avflash.nl/upload/files/90972840677.pdfIn PDF document text
    • http://dvif.fr/userfiles/file/xumiputufoxaxoburifiwoxaz.pdfIn PDF document text
    • https://sergiomauri.com/images/file/dilubikebadalum.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/rekawibox.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/29eu04i2u54t7ij6i7drp4sebd/motirotaduj.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16137e05de5d30---52501475821.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/boruzaxavepulapa.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/92sd8dkbm2er5h1jbv8uh59q1g/simajobikipe.pdfIn PDF document text
    • https://dadrarad.ro/userfiles/file/96659975313.pdfIn PDF document text
    • http://jeanchapleau.com/userfiles/file/vewofipiwuxaradobavevil.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/36e899ed3170ee85e133cb3b74c68287/88128992574.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae3d91ba70---damalebowetofimetumuka.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/xuperijirisuzidozik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=airdrop+between+mac+and+androidPDF link annotation
    • 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_off0000df18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF18 17920 bytes
SHA-256: 6f17fb85dd3610bda3b6b99cd0e28b323b2e671b3c0340d276ff3d6dc8fef70e
font_01_sfnt_off00010d20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012537.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12537 10668 bytes
SHA-256: b79ed553a2639068950c6f40aeff0c2367ba51728a72ea7078c4bd627b0dad89