Malicious PDF — malware analysis report

Static analysis result for SHA-256 255c72e2c3a4b5f1…

MALICIOUS

PDF

69.3 KB Created: 2021-09-18 20:17:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 0c2ba0c7609109afbf1ae10d406c136d SHA-1: 8b74afbacc4dc83525a94a8582fc909a5c665153 SHA-256: 255c72e2c3a4b5f15696e510c4963de38117ab04a45828bf77194462d70a9889
96 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, suggesting a link farm or redirection scheme. The ML classifier strongly indicates maliciousness, and the presence of external links aligns with techniques used to distribute malware or phish for information. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond what is inferred from the URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://pixomot.ru/uplcv?utm_term=gta+vice+city+apk+download+for+android PDF link annotation
    • https://christianklein.eu/Quansis/ckfinder/userfiles/files/texuzuzir.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135fb521ec25---12602602172.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/tewopifigopatanowubixavaz.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/nanebupax.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/161307ea068e3d---2265597841.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/955264ccb5fa1f33da4f68fc96fbbffb/zesitarozotodisudizovuwu.pdfIn PDF document text
    • http://holdemigny.fr/ckfinder/userfiles/files/dabikilenuleridobezomatom.pdfIn PDF document text
    • http://koreabulk.net/userData/board/file/gezamaduvolurop.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613566d92eccb---zivasudabevemixilaran.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131f2b713094---venakikazotemusuziweke.pdfIn PDF document text
    • https://cairparavel.ro/app/webroot/files/userfiles/files/lizivolenitexasewudu.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/8075797832.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/dobanibumoseraralax.pdfIn PDF document text
    • http://studiotrusso.it/userfiles/files/54921603939.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/rutosa.pdfIn PDF document text
    • http://industrialdevices.in/uploads/6698213822.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/24259604343.pdfIn PDF document text
    • http://tipiland.net/upload/file/bivibolobamulotexemuzimu.pdfIn PDF document text
    • https://ikincielinmak.com/upload/ckfinder/files/14829074834.pdfIn PDF document text
    • http://onfireinteriors.com/userfiles/jelavovinimex.pdfIn PDF document text
    • http://forepic.com/_UploadFile/Images/file/22385574517.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/bavadenejutorufede.pdfIn PDF document text
    • https://kermanrooz.com/img/files/92762101705.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_off0000b231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB231 10840 bytes
SHA-256: 3aa3f4a46624f2d64e54a368e535ccc7bd97da1e2ddf85faafcad5e43dc6a89a
font_01_sfnt_off0000cb75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB75 14344 bytes
SHA-256: c58a11f204809f46c11a5ef45adc555de3e8adb6da4c0932cb63161a9b5540b4
font_02_sfnt_off0000ef28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF28 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1