Malicious PDF — malware analysis report

Static analysis result for SHA-256 9444ca90c5da61f1…

MALICIOUS

PDF

88.1 KB Created: 2021-08-09 13:53:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: fa42d450c7b56fa34c813fa65075772c SHA-1: d3a7e2e6666841ca139328cf08c7d18868b4da9b SHA-256: 9444ca90c5da61f1c597506aa541124edcc5cfa20a45bc912b5856c72e66a7f3
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identify it as a link farm, with numerous embedded URLs pointing to compromised or disposable hosting. These links likely serve as lures for phishing or to distribute further malware. No scripts were extracted, but the PDF structure itself is designed to redirect users to external, untrusted sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://babamoleskine.com/files/file/kaxonuvokomope.pdf In PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/b661ba546f120004ed39717f7fc215a5/63810767037.pdfIn PDF document text
    • https://mk-promotions.com/ckfinder/userfiles/files/loguvugebegajirobasepi.pdfIn PDF document text
    • https://autoteam.in/ckfinder/userfiles/files/21729490638.pdfIn PDF document text
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/a000948bddd9883bf9d0f4be61af05b2/jusub.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607738faa35f2---jumalevu.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/ba997cc574ffd8a6502594fe435db05f/11330213821.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/10273105478.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/30940309507.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f904f35076---watudasatapapote.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/mibozubenin.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/0274cb0c3692c367e810ccb1ff389c23/bigegotexawod.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160f05b578524e---96522328552.pdfIn PDF document text
    • http://mintaialuminum.com/d/files/fatoxaruv.pdfIn PDF document text
    • http://karunb.com/UpLoads/files/wuzulibewobijog.pdfIn PDF document text
    • http://pes.edu.mn/ckfinder/userfiles/files/60757864100.pdfIn PDF document text
    • https://baptistfriends.org/media/61716471528.pdfIn PDF document text
    • http://kistours.hu/userfiles/file/kipowotutun.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/3274792077.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/11518290118.pdfIn PDF document text
    • https://ivaco.it/file/xibami.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dcd0e653ca---56703534057.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/gs8jjfoub6ltv0brlmc9dnajuv/radudigebu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=business+communication+skills+textbook+pdfPDF 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_off0000f04e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04E 11168 bytes
SHA-256: f38d60b3988a67870930cfb1d2562e856ed590d69a79e4475bdccf879b49adf6
font_01_sfnt_off00010a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3B 18376 bytes
SHA-256: c1172eeb2220ecc363dc91321e1a430f58ce41d06e67df5d5b9d069df33c1fe3
font_02_sfnt_off000138f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1