Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4708b64d0cba691…

MALICIOUS

PDF

82.3 KB Created: 2021-07-03 02:26:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1fe66438426a4c7292cae1af065ab1e5 SHA-1: c2ae563b15f0d1561d4b1800332fa366d609a390 SHA-256: f4708b64d0cba691a2ed3e74544e6703283317aeb0f47a5da59d5b5894d9ac1d
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many of which point to compromised WordPress sites, specifically within form upload plugin directories. This suggests the document is designed to lure users to malicious or compromised content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607180134a4cd---78411505859.pdf In PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/c4c1f3cf1d5126c3b3a22f9b37c7e597/26040178481.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/4mfuer2pgsohm56lpdpbn6mu04/3949582413.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/zutujunawudifos.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/tcop937rt60jh51qg3re3ujv4e/11773242454.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/66176594533.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160982eb06b967---vikulikenagire.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce8198c815---nufibal.pdfIn PDF document text
    • https://antae.be/app/webroot/uploads/file/34558546840.pdfIn PDF document text
    • https://advik.net/userfiles/file/rewutijufaxetisowuku.pdfIn PDF document text
    • http://bhavalaya.org/ckfinder/userfiles/files/finisiwedo.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/215046b66494ba14205abbd9594a8fd3/17146089540.pdfIn PDF document text
    • http://7tec.ru/userfiles/files/42255870069.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/011261fe855ad5c93b1208c3aa26632a/pugadesij.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/28cd17dcb911c029f307cb89d937881d/keduseneverew.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/da845e1b9b87dcc9cfb726591580257b/37195072303.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16075bd2c88c6f---29512925305.pdfIn PDF document text
    • https://mangmalungtea.com/userfiles/file/bibaf.pdfIn PDF document text
    • http://ge-mak.com/files/72331269739.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/jevisaj.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/0r90nc7egjb1vtnom41dpico0e/64514526625.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/jaxaxikurebi.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/17561287606.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/29004482624.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/3c1b69fbcfbba3736cb96aa63aa024be/22037022766.pdfIn PDF document text
    • http://ithaca1961.com/clients/875375/File/22798047806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=bootstrap+center+in+divPDF 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_off0000dd87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD87 17564 bytes
SHA-256: 91398a21243b2e52ec4e245c61b26cfb8383bd7cf043523ca7e1df5bb1738702
font_01_sfnt_off00010b90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B90 10580 bytes
SHA-256: ba8c2bb191fc9e25e2f4773bf116c3787fc36f0eb0fd954401514eb3b6ce7126
font_02_sfnt_off000123f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1