Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7d88fb1dc07b214…

MALICIOUS

PDF

82.8 KB Created: 2021-09-18 19:25:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2bce5fc1a5209ab33e24e2ca538dfb0c SHA-1: 45bd5e3004266aceb5283e8e110cf891cfba511a SHA-256: b7d88fb1dc07b214a6c079f16737cecd80db798199bef381ff4ba172489176b4
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to potentially compromised websites or disposable hosting. The document body is heavily obfuscated, preventing analysis of its direct content, but the presence of numerous external links strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://aawyx.com/sites/default/imageuser/file/18053259179.pdf In PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/4ffafe59ee9042988dec1a23e88db3af/16277882929.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210905_161942.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/litidilizakufu.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161335c860e4cb---defekorajiladidopi.pdfIn PDF document text
    • http://vcelari.naceradec.cz/includes/ckfinder/userfiles/files/72020053765.pdfIn PDF document text
    • https://bevillelecomte.ovh/ckfinder/userfiles/files/7005779820.pdfIn PDF document text
    • http://preprod.app-nomads.com/ugecam/admin/ckfinder/userfiles/files/53938418280.pdfIn PDF document text
    • https://egf.tw/test2/images/file/59433919504.pdfIn PDF document text
    • https://lingchuanfloor.com/app/webroot/userfiles/files/jininox.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/newofadizowikorukem.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/c42e44f43482ec907126700b50aeb2f4/dajalezituzalopamepopum.pdfIn PDF document text
    • http://constantemail.com/userfiles/file/1631925116ginanopiruxopurotore.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/kasemipuzuxapikefako.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/tawawukugona.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/10354455825.pdfIn PDF document text
    • http://briquettemachinery.com/d/files/6033221174.pdfIn PDF document text
    • https://luckysurface.itweald.com/uploads/files/6138b9aa89574.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/32965003354.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/25837368526.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fodojupetelilusurave.pdfIn PDF document text
    • https://ssekolkata.com/ckfinder/userfiles/files/lomamewiravojolexadelazot.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318e215bcea---9760899896.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=android+en+iyi+resim+d%C3%BCzenleme+program%C4%B1PDF link annotation
    • https://unimedbelem.com.br/painel_template/assets/global/plugins/ckfinder/userfilesfiles/47785599163.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_off0000dde4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDE4 11028 bytes
SHA-256: ff28a403f880d1054292f17d3afff3eafbfb23e0ef5dcf1e7aaf5c2d3e8d2260
font_01_sfnt_off0000f736.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF736 17992 bytes
SHA-256: 09dd41aa762ddf185aa8fb530cac7c18cb190acbf2c20330be65be42b5ee9ca1
font_02_sfnt_off0001236b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1236B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1