Malicious PDF — malware analysis report

Static analysis result for SHA-256 875d6a167d6a7416…

MALICIOUS

PDF

80.9 KB Created: 2021-10-02 20:03:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a3e9b6f56a7c862e81eb83516f674604 SHA-1: 1a795bdd461f80d5a16dcc1289bea4aab8fb4255 SHA-256: 875d6a167d6a7416823291aaba5087ff24def0a2239ef9f87ba0c1b1288c39d3
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to other PDFs on a variety of domains, many of which appear to be disposable or low-reputation. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a deliberate attempt to create a link farm. While no scripts were directly extracted, the ML classifier strongly suggests malicious intent, likely to distribute further malicious content or for SEO abuse. The presence of external URIs and the link farm structure suggest a spearphishing attachment as the likely initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 4

  • 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://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/upugt6j6m8i0v9937hojln1ru0/70803393391.pdf In PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/58745591241.pdfIn PDF document text
    • http://byecook.com/ckupload/files/jalivamajobef.pdfIn PDF document text
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/4324077769.pdfIn PDF document text
    • http://citysoupsbellevue.com/uploads/files/wonajolon.pdfIn PDF document text
    • http://eros-arena.com/eros/userfiles/file/71680622120.pdfIn PDF document text
    • http://adasbruiloften.nl/userfiles/file/19123742300.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/tinubibumite.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/16000494258.pdfIn PDF document text
    • https://babamansurkurhuseyin.com/uni/yuklemeler/file/romitipisemovufamudidumo.pdfIn PDF document text
    • http://zjbfjt.com/upload/files/zukepavenumekalatev.pdfIn PDF document text
    • https://watfordfairtrade.org/app/webroot/img/files/jenodin.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/medijiruwofojimijo.pdfIn PDF document text
    • http://www.polni.si/Images/files/refinusifinawiwefe.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/83359950818.pdfIn PDF document text
    • http://sirmamedia.com/ckfinder/userfiles/files/54861034787.pdfIn PDF document text
    • http://irinabailey.com/upload/files/bodufelojijekijojokaromi.pdfIn PDF document text
    • http://lasermedia.cn/userfiles/file/93385146619.pdfIn PDF document text
    • http://www.bash.cl/media/file/rizerebawivodizedilez.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/57260900691.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=length+of+men%27s+size+9+footPDF 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_off0000d42c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD42C 10572 bytes
SHA-256: 804186747fe2762b67ed13480c7dfc658936f98067da862515a8404e9c742941
font_01_sfnt_off0000ec39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001044b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1044B 19004 bytes
SHA-256: 602e57af7b11a69cc8f8da883400eac8a8b1a8095fa24d013aa6d65970fe7465

Open this report in the interactive analyzer, or submit your own file for analysis.