Malicious PDF — malware analysis report

Static analysis result for SHA-256 53b118feeb0d729f…

MALICIOUS

PDF

84.3 KB Created: 2021-09-10 11:35:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 170d3df87e00a7af1761178fde369f05 SHA-1: 574b802ef11d163581577dca41cf23851a0b2532 SHA-256: 53b118feeb0d729fbee6a678723eda1c2307f89ea2915792163278ff9809b764
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the presence of external URIs and the link farm structure are key indicators of the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://coretry.ru/uplcv?utm_term=watch+yes+god+yes+2020+online+free PDF link annotation
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/161316da4bab36---gogagovenisogidikivekabax.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/vepusivazejejimoteziris.pdfIn PDF document text
    • https://turdv.ru/SITE/files/editor/file/rafejevizexikiworevotozu.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/ce562bf2e67c8f708de3a1e935448c22/11934786595.pdfIn PDF document text
    • http://studiofapas.it/userfiles/files/62144841948.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/49302979858.pdfIn PDF document text
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/40579221652.pdfIn PDF document text
    • https://armenia4d.com/contents/files/14857048057.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/52961745303.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/bofafinuvukejepaf.pdfIn PDF document text
    • http://bantinnhadat.com/users/files/94219477032.pdfIn PDF document text
    • http://aquaclub.hu/userfiles/file/pazemutuj.pdfIn PDF document text
    • https://elearning-chemistry.ro/userfiles/file/jabebavajan.pdfIn PDF document text
    • https://fullprotec.com/ckfinder/userfiles/files/11704998263.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16139f4be67e36---zerikoraxavobibevugig.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/diwuzujalofof.pdfIn PDF document text
    • https://yuktogel.com/contents/files/todusukukugozu.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/zovarobunu.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/161355b2463684---netoxopeko.pdfIn PDF document text
    • http://pk-rowery.pl/user_pict/file/vemaxekepepekuletubib.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/fanud.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/50463262124.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/sipojexufawat.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613107f0a30c3---sutisubagujufujuzufesiva.pdfIn PDF document text
    • 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_off0000e3e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fbf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBF9 17724 bytes
SHA-256: 248bd2112753b4f4f12fb4c26326f91c8a1d1a4bf25c13ea256c04cc5f6e5bb6
font_02_sfnt_off00012a2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A2E 11104 bytes
SHA-256: 3865084cdd8373fb7739465ca3bfa0fd2d0c7aa16a8ea5638f93a879d95293aa