Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bcea1d8700cf9c5…

MALICIOUS

PDF

79.2 KB Created: 2021-09-24 23:51:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 47d3379e2b2a5f8d7d5eb8fbe1c77f24 SHA-1: 2b37f92e08d7643c9b70c59b89a6487f32381f0f SHA-256: 7bcea1d8700cf9c54e3d8cb845a33fc16ca858f5ea1e4e629eb8b933e15efb1f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads and disposable hosting. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose, which is likely to direct users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 http://simp-q.ru/userfiles/file/tevederexogi.pdf In PDF document text
    • http://taihegas.com/filespath/files/20210921051137.pdfIn PDF document text
    • http://plymouth-logs.co.uk/ckfinder/userfiles/files/84180955168.pdfIn PDF document text
    • http://technestudio.eu/userfiles/files/92318367138.pdfIn PDF document text
    • https://satbietthu.com/luutru/files/10394048617.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210918185744_m1ev6w.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/161461bf0bfcbe---beperepeninexijumoremorab.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/4186862378.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/60317006211.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/jodamadipikawixutogax.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210903122908.pdfIn PDF document text
    • http://batterseataxi.com/survey/userfiles/files/safafure.pdfIn PDF document text
    • https://aiwcecckolkata.org/FCKeditor/file/37929785063.pdfIn PDF document text
    • http://unewstoday.com/task/userimages/file/16651919549.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/boxuxazotewodedobup.pdfIn PDF document text
    • http://workontext.ru/media/file/mefukujexatenifowevixega.pdfIn PDF document text
    • http://open.ua/uploads/ckeditor/files/15031466724.pdfIn PDF document text
    • http://globomax.eu/userfiles/file/95533712897.pdfIn PDF document text
    • https://dimensioninteractive.com/WYSIWYGImage/file/zemokabomewifamu.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/74178280152.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/7648549a335bec32ae14567fb0178bb5/9100281109.pdfIn PDF document text
    • http://tokyoto.pl/UserFiles/file/79568155845.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/46240619249.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a848039b59---fowademejobi.pdfIn PDF document text
    • http://theclelandgroup.com/img/upload/file/kixezi.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/89543435426.pdfIn PDF document text
    • http://iscyber.com/userfiles/files/zadowerelofarejebur.pdfIn PDF document text
    • http://primeasset.hu/fileok/file/80389055983.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=recovery+video+beta+apkPDF 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_off0000cc6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC6E 10648 bytes
SHA-256: 06ad771e6efd9544283a38506b85d6165dac710d037988ecc4876eb599aac6ba
font_01_sfnt_off0000e4c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C3 19344 bytes
SHA-256: 93960c906552b042a7276334f79ce02d46810796a4efa03f0e06e24c1a1d1a33
font_02_sfnt_off000116c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1