Malicious PDF — malware analysis report

Static analysis result for SHA-256 525db14793fc6104…

MALICIOUS

PDF

83.0 KB Created: 2021-09-16 10:32:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ce725c13340e61aae15767cc72e1aeb0 SHA-1: b5e7f5dfae5eeb91b3457885224cc268391fc18c SHA-256: 525db14793fc6104772c2117c2d21335ca9eead7f033da9ae95258f4e18e91fa
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The presence of 'utm_term' in one URL suggests a phishing or SEO manipulation attempt. ClamAV and ML classifiers also flagged this PDF as malicious, supporting the assessment of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://krisoc.ru/uplcv?utm_term=viber+cracked+apk+download PDF link annotation
    • http://biblioteka-belzec.pl/upload/files/lakaravokowu.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/63915183590.pdfIn PDF document text
    • http://gensugroup.com/upload/files/zefaka.pdfIn PDF document text
    • http://psn-monolit.ru/img_file/files/mikoxuwakofikux.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/e0d695766ed6a183db6f12a1316ded27/82346178702.pdfIn PDF document text
    • http://millionsdiscount.com/mo_images/files/27091913723.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/lakoregatiwudumalu.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd55010584---xezor.pdfIn PDF document text
    • https://clic-essc.ch/ck/ckfinder/userfiles/files/92347944509.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/14816776398.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/c9bf03ab0d022df5d4cde42ba5265023/46740419677.pdfIn PDF document text
    • https://theurbanthinktank.com/files/majabivudazo.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386a0da0d12---24472950150.pdfIn PDF document text
    • http://placc.info/up_image/28759794817.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/xixufapijir.pdfIn PDF document text
    • http://srtcivilnorth.com/ckeditor_file/files/vajisinisumejuvekodena.pdfIn PDF document text
    • http://kietminhrivet.com/upload/files/sudolowixake.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/zoviwebipajag.pdfIn PDF document text
    • https://v-rshine.com/upload/images/files/74116682706.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/54357686998.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/677munu60buiubv8mlqigal5e2/9976189687.pdfIn PDF document text
    • http://studiolaviano.it/userfiles/files/13985257492.pdfIn PDF document text
    • http://veterky.ru/ckfinder/userfiles/files/60595988548.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/fekibudagexij.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/11676411924.pdfIn PDF document text
    • http://shijijiaming.net/filespath/files/20210908091546.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_off0000df43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF755 18044 bytes
SHA-256: 4b1fc66b29c6c40f8227254c9de9aaf3b39a557a957f7ddb680a1abe490b6a91
font_02_sfnt_off000125f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125F6 10528 bytes
SHA-256: 99762ae790bb38d8c39226ad753406dc876f5866ef5acad8015a29945740f12c