Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f1351f6c5ee8cfb…

MALICIOUS

PDF

83.7 KB Created: 2021-09-22 11:03:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b22655cff15f03e9fc1774375a89f255 SHA-1: 464f4432ff2eca27820f353eef3e9d94060e8328 SHA-256: 4f1351f6c5ee8cfbff86d8c966db233ebf1614d33a592fb38e9707d1c9cae01d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://puzynowska-kancelaria.com/userfiles/file/82519335962.pdf In PDF document text
    • https://cornerstonelaw.eu/userfiles/file/kosenuw.pdfIn PDF document text
    • https://gazeta-msp.pl/user_files/File/27959642311.pdfIn PDF document text
    • https://pasifikendustriyel.com/userfiles/file/45849984706.pdfIn PDF document text
    • https://hoalavender.net/upload/files/29704608728.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/sasimaki.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141765e70a39---letasivajeduju.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/0pm8073a4c5evvhuv745j95j71/posemivisumir.pdfIn PDF document text
    • http://linza-market.ru/upload/files/dotimosesexonegufe.pdfIn PDF document text
    • https://anninhsieuthi.online/upload/files/gefejemunixuvale.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/65388046229.pdfIn PDF document text
    • http://minhnguyenvn.com/uploads/userfiles/file/tuseminojuduwalimufa.pdfIn PDF document text
    • http://skisun.it/userfiles/files/nameju.pdfIn PDF document text
    • http://pedraferro.com/files/files/ririvupuladebewud.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/gogejumawokuwisapeturosi.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/37506366966.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/93563134284.pdfIn PDF document text
    • https://mediaget.ru/userfiles/files/favowowewadubuf.pdfIn PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pabetugiwumo.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/4b67de48fd2f190e26a14010b63fa4ee/1431000951.pdfIn PDF document text
    • https://swaarm.de/app/webroot/upload/files/ludizaranaxawikusibijud.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/55553659068.pdfIn PDF document text
    • http://www.alcera.ca/userfiles/file/23451319193.pdfIn PDF document text
    • http://canavesiobruno-architetti.it/userfiles/files/tefajevibonowebagerob.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/lizemowebadezufiju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=magic+background+eraser+pro+apkPDF 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_off0000ddf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f60b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60B 10868 bytes
SHA-256: 24285c313867c2a2ad9e67bdcc05bb12b92de79f074c47463e3950ba83979999
font_02_sfnt_off00010edf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EDF 18964 bytes
SHA-256: 0abc5ec0263c14455bc76d33fa0f319ef00ffc191b66025112a475972cc1cc3a