Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8dc452a73ddfad4…

MALICIOUS

PDF

95.1 KB Created: 2021-06-30 20:24:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7186e4f16c5b056cc7f8e5bb9c709a4e SHA-1: 0ce27c0e44aa4f01118190ef2d3fda9229c80090 SHA-256: c8dc452a73ddfad42101857205dd98223676a9526a2bb1f30d74eea742299284
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm heuristics point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3c9773237---zivevakok.pdf In PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b6c7c59d6ca---nupisodupanigixarogek.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160749666d09bc---bidarevexi.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f24542771a0d5a86e7ed00c3ac8ebac4/pizilibuvatufebu.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/32f2f64fc0e2e27721f37880a4432ca9/korenagiriwusedegifazeso.pdfIn PDF document text
    • http://mesahighclassof63.com/clients/79820/File/89714118156.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ddc440c49---nitavirowopitogidunuzat.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/68191852092.pdfIn PDF document text
    • http://sbox-technology.com/upload/datoteke/58772070319.pdfIn PDF document text
    • https://eobliecky.sk/userfiles/file/28233131837.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/b3fe97f8db55b0c256d0b78d15975ca5/befowujebib.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fcab36dcd---kokepufisofutisunuv.pdfIn PDF document text
    • http://nowyhotelik.pl/userfiles/file/61246614144.pdfIn PDF document text
    • http://jirehenl.com/userfiles/file/162047211769.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160883710dee77---58113741777.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160806cfb403e0---xeramuxewo.pdfIn PDF document text
    • https://daismene.it/file/76043960415.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608628bbc87a6---83566513051.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160823283a1555---50680051736.pdfIn PDF document text
    • https://dodatnojamstvo.com/userfiles/file/puzuwokexasi.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/serofizuxuxuzepusenofupaj.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb881a2ac1---57356753068.pdfIn PDF document text
    • http://protectname.xyz/whoisprivacy/userfiles/files/tusozezodidutemaxiwuset.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e85587918d---kixegadonopenabulagobus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=book+recommendation+websitePDF 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_off00010fa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA4 10856 bytes
SHA-256: 26eef76f9b2e644d21a99b96080f7cbae7b14fa619a56d3d672782e066c58464
font_01_sfnt_off000128d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000140e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140E7 17740 bytes
SHA-256: dd0f41a8bcace8c7051269320b5e56b138f6d644cae8d34356f7d36cfe4c9a9e