Malicious PDF — malware analysis report

Static analysis result for SHA-256 d63b173f337cb3f9…

MALICIOUS

PDF

70.9 KB Created: 2021-10-06 00:24:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 323e914291438baeca1ff9b2c8c685cb SHA-1: 8449463782d53fd1469438e54c37bb85819ead8d SHA-256: d63b173f337cb3f9630aa2b20345de9a62335b5af6dddae3d4f4e1f7edad6e43
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an effort to obscure the ultimate malicious destination. The document body is unreadable, but the heuristics strongly suggest the file's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://stabiactiv.com/userfiles/file/45618140729.pdf In PDF document text
    • https://drrajanmahtani.com/userfiles/files/89244870415.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210926_05D929B0F854BBA8.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1614e8e7ee549c---namutekuxamofaravig.pdfIn PDF document text
    • http://sangsangins.com/upload/upload/file/wemojovixakavemifiwe.pdfIn PDF document text
    • http://pcccmiennam.com/media/ftp/file/84159957800.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/5696aadbd9b5a1a825aa007b65c5a20e/satusufadokoweberi.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.net/ckfinder/userfiles/files/71148325094.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/nefifefifumanuziravaji.pdfIn PDF document text
    • http://kozelsk-adm.ru/files/uploads/files/nawabovobaroxiboje.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/69194543711.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133d6da23ed5---xutidej.pdfIn PDF document text
    • http://studiotecnicolari.it/userfiles/files/sawepinibe.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/tumutolewudetodajunavo.pdfIn PDF document text
    • http://pronobile.com/catalog/file/jowuduruv.pdfIn PDF document text
    • https://pragatitic.org/ckfinder/userfiles/files/45779728270.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/82112492127.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/13320943761.pdfIn PDF document text
    • http://taispacedesign.com/upload/files/wetunusoviw.pdfIn PDF document text
    • http://greathorserider.com/ckfinder/userfiles/files/19238847821.pdfIn PDF document text
    • http://giaydantuongphongkhach.net/images/news/file/buxufumitelanetuxisis.pdfIn PDF document text
    • http://wirheiraten.de/images/file/zadiwumogufusosap.pdfIn PDF document text
    • https://xn--q3cceuw0c6ab0d2ii.com/upload_file/files/23294511865.pdfIn PDF document text
    • http://3234.us/data/attachment/file/76157033246.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=severely+atypical+nevusPDF 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_off0000b5bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5BC 15816 bytes
SHA-256: b035aecb17912178d553316129a96c1b1c0267de30fcc37ce10aff5f258a5cc7
font_01_sfnt_off0000de06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f61d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61D 10604 bytes
SHA-256: cc0d1c9ba10ad87d44a122f1c0388a78941b8ecdcca26b53538c5bcc740ebc7d