Malicious PDF — malware analysis report

Static analysis result for SHA-256 330c64729902fb77…

MALICIOUS

PDF

91.0 KB Created: 2021-07-31 14:53:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: bcafebc3cd5c863931e86040ff43a047 SHA-1: 06f3d5cb95c1d27d4fa52be6390896f334935cca SHA-256: 330c64729902fb7704c18ebcd012d7fdb30da0b65b7d585c85b211cfb7f9027d
96 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on various domains, many of which appear to be compromised CMS uploads. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, but the overall structure and heuristic firings point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 5

  • 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://pelletier-tp.fr/ckfinder/userfiles/files/95567907403.pdf In PDF document text
    • http://parkwaywest1974.com/clients/861606/File/pasipaguxevuri.pdfIn PDF document text
    • http://engineersclasses4competition.com/files/others/98156258187.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/9ejkaab0soja1mah9j61s8aitf/28510659785.pdfIn PDF document text
    • http://sicompk.com/survey/userfiles/files/31215937195.pdfIn PDF document text
    • https://emprenderem.cl/files/buvezekewiduxakufogefetil.pdfIn PDF document text
    • http://theleadershipworks.com/PO2/UPFILE/userfiles/files/26607990286.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/48753992073.pdfIn PDF document text
    • http://growlink.biz/userfiles/file/pasinuvidajomibava.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/lscte16c6ud6781tb79jmdtl0g/19680358459.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccbbb98122---makesij.pdfIn PDF document text
    • http://nyett.hk/uploads/news/files/98700148104.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/2753925802.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/av4jeescondmknd6664rd9qmj1/gavegirodipevavow.pdfIn PDF document text
    • https://tbsva.org/Upload/files/20210703024354.pdfIn PDF document text
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/sotojafupupetixudifum.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa7867f090---29487359828.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/nkdsreoldh551fi5l81105p0f1/bevidavafemo.pdfIn PDF document text
    • https://liffeyartefacts.com/fckimagefile/file/pijataxomekonip.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc45ad4ef9---ditukopojubojonupok.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210521021947844824195.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/8nvf24hftk4uvv1ep1sg1nv9g9/3443539448.pdfIn PDF document text
    • https://itacademyindia.com/ckfinder/userfiles/files/logenanolix.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/a215bf95785119a04179adb0cfdd38d7/votaberafurubukexedusu.pdfIn PDF document text
    • http://sumterhigh89.com/clients/863574/File/mezimumurafowepasumorulod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=castanha+do+par%C3%A1+benef%C3%ADcios+e+malef%C3%ADciosPDF 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_off0000fb27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB27 18904 bytes
SHA-256: 7816816140c8f5a460e9bf8040991ac1714e5b7e4564e23b403b67f990364027
font_01_sfnt_off00012918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12918 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001412f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1412F 11296 bytes
SHA-256: fe7f51fbe40ea111582c37d11c2c4af1dc19b62fb31d003c8a844aeb200d01b6