Malicious PDF — malware analysis report

Static analysis result for SHA-256 0643e53663934208…

MALICIOUS

PDF

71.6 KB Created: 2021-09-26 11:09:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2f0a6d7430c510ba5dc3eaa5bc13b1c7 SHA-1: 7649310aee76a8ccf5e0d0d7861f0c81591e5eef SHA-256: 0643e536639342080cb60efb2e1f499f132b06cd8cc27213a7b7a74227aa0a87
96 Risk Score

Malware Insights

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

The ML classifier strongly indicates maliciousness, supported by heuristics identifying the PDF as a link farm pointing to potentially compromised websites. The embedded URLs, such as 'https://allytemp.ru/uplcv?utm_term=refactoring+improving+the+design+of+existing+code+2nd+pdf', are likely used to redirect users to malicious content or phishing pages. No scripts were extracted, but the structure and URL patterns are consistent with a document designed to lead users to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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://allytemp.ru/uplcv?utm_term=refactoring+improving+the+design+of+existing+code+2nd+pdf PDF link annotation
    • http://titadoorbinhduong.com/upload/files/bidanebukuganolosed.pdfIn PDF document text
    • http://aatmicscience.org/asuserfiles/file/93472456365.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/zumelofewulugujen.pdfIn PDF document text
    • https://sharmtocairo.com/userfiles/files/83501657378.pdfIn PDF document text
    • http://thanhtindesign.vn/uploads/image/files/sugujigad.pdfIn PDF document text
    • https://harom.ro/files/file/19341755499.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109040548446445.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/491b2a1491bcffab8272a2d7f0f29980/wabererukafugozujop.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/91951852277.pdfIn PDF document text
    • http://celyroknaterase.sk/editor_uploads/system/files/gosexag.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/37167306119.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/95408031089.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/10707362197.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/99ub6rt0c39g30c1mjeveqmu2v/23276438862.pdfIn PDF document text
    • https://beauti-full.ru/uploads/files/majuziramonuzoli.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210902201012172.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/4961411bef2330dc6ddc5b0c8dc6297e/rusexukevoturobojup.pdfIn PDF document text
    • https://okazionche.com/files/melop.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/42653763745.pdfIn PDF document text
    • http://bowlingkillers.com/imgdb/files/59880583447.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/viriguniwosijewefizugafi.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/51853719018.pdfIn PDF document text
    • https://www.phuketvillarentalandservices.com/ckfinder/userfiles/files/bijeputuzaletaxu.pdfIn PDF document text
    • http://mqskin.com/luutru/files/89603603656.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_off0000b259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB259 11352 bytes
SHA-256: 8dd4000748f7f67588a4cde01acd6b4bde86957040ffbc4488526eb9a1f07c18
font_01_sfnt_off0000ccc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCC7 17208 bytes
SHA-256: 2553afa9c41c5c2283d222121edb68f834d66603a29cc5c1cefc5a211ba217dd
font_02_sfnt_off0000f836.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF836 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1