Malicious PDF — malware analysis report

Static analysis result for SHA-256 845d7a9057349f8a…

MALICIOUS

PDF

85.4 KB Created: 2021-09-04 22:19:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 38cce7a62a7405898a0e9a76ff4dbf15 SHA-1: a895dabf7032e73c31a20db7ae841eca554fb8c6 SHA-256: 845d7a9057349f8af4da4b2ef6aae8c36949651f72618c8378fb2333de5c0ed5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to malicious content or exploit kits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9765

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://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/ttvisbro6o2veung861olj25bk/sarosalovimijejixarapux.pdf In PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/82656325088.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/xuxadugalefa.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/nugedisitumaw.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb3855b990---wabujenuw.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/39470678010.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161214bc9602fe---38143737711.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abeaef3e387---jorufeletiwanipatomuraju.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/485407a69cf3e380639497ad2cb38952/jarudurevapakorawodukus.pdfIn PDF document text
    • http://ping-property.com/user_img/files/73926111790.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/gulanitipademopuvegexa.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/379726054f84b2a920d627f5825dc8f2/banubenufereki.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/38565518704.pdfIn PDF document text
    • https://ou-ravda.com/ckfinder/userfiles/files/soziponebuloki.pdfIn PDF document text
    • http://royalwedding.jp/images/blog//file/vujisolosuzekomadaduwoxu.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c85c0abee7d---65265490261.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210530224942_1958099624.pdfIn PDF document text
    • https://birotex.rs/images/files/12498150070.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160d5fc14b4933---93402364043.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/d1a2bb0577a542739fdd485e94387bcd/48484121556.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/285904efad2461f9225241866daa3142/95373367978.pdfIn PDF document text
    • https://club-sports.net/uploads/products/files/15651037246.pdfIn PDF document text
    • http://dancedynamicsla.com/clients/38740/File/zaminefujirefapunini.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210521021947844824195.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/369563b04d1b397e287edf6d40436705/10421414482.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/2j21fc6rutpqmmf2r51bjstoj3/14654346164.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=maths+word+problems+year+5+worksheets+ukPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000fc8e.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xFC8E 18360 bytes
SHA-256: fe6a030cce3a1e6f7bc0bd98ffaf71e5932d07356b5efb165c677cd9129ebadd
font_00_sfnt_off0000ca8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA8C 11120 bytes
SHA-256: f36aa30535df4ade7097ca6a13ed715cc2215513ad07032ae950c2e299f63b63
font_01_sfnt_off0000e47d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000118d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118D8 17528 bytes
SHA-256: bc490532c1f3d34f541637f98f80c065088465803584167760ab2045670f4386