Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8b98228d5a4b109…

MALICIOUS

PDF

77.0 KB Created: 2021-03-16 09:50:35 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 13b782ed95cd9976cf956aee8fa1e011 SHA-1: d5aa325e6a101d19af70f08330b2c1a628154b48 SHA-256: e8b98228d5a4b10963fef229b45b1351a88995d5cd682da70c9b7806cbded159
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many pointing to benign files, but at least one redirector URL (https://leonvi.ru/wix?keyword=prepositional+phrases+as+adjectives+and+adverbs+exercises) is used to lure users. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external links, suggesting an SEO-based lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://leonvi.ru/wix?keyword=prepositional+phrases+as+adjectives+and+adverbs+exercises PDF link annotation
    • http://devicesprotectionforusers.site/48714738737q3hhy.pdfIn PDF document text
    • http://tipofeliluget.medianewsonline.com/86443784934.pdfIn PDF document text
    • http://rimarilomikozu.medianewsonline.com/48852495904.pdfIn PDF document text
    • http://carinsusa.info/spanish_food_dictionary38if6.pdfIn PDF document text
    • http://lebedugipul.mywebcommunity.org/astm_construction_standards.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/leteraxewe/mojuseru.pdfIn PDF document text
    • https://21d44941-995c-48b9-956b-8145330e20d5.filesusr.com/ugd/577b75_5ec1bd0d9e5b40f281e89e2836967040.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/naxozelozude/netgear_prosafe_gs108t_default_ip.pdfIn PDF document text
    • https://s3.amazonaws.com/wolawatin/duwimiposudutodis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20463e8a-da82-42a8-ace2-1783a3ccb2dc/mepunakebivapoxirezipiza.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65e31464-e6a4-4d1c-b197-c5292a6a66e1/katuzusevo.pdfIn PDF document text
    • https://s3.amazonaws.com/wurivuve/83807299168.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2fdb84e9-7a8a-4c7a-8d06-b90cd3209c10/jugululazede.pdfIn PDF document text
    • https://s3.amazonaws.com/pogolo/gujep.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c2e7bbb-66e8-4f59-b2f4-d4a93a5b3e37/pioneer_ddj_sx2_controller_price.pdfIn PDF document text
    • https://9e2bb560-353e-4f5d-a08b-1363560edab4.filesusr.com/ugd/6c032c_faf381c937794390acb3c51093557bc8.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/banula/25606420630.pdfIn PDF document text
    • https://s3.amazonaws.com/vibuvomomuv/safativemi.pdfIn PDF document text
    • https://b724dda4-e2e0-47c5-811c-ae3b7273578b.filesusr.com/ugd/a1e5ee_97e3e532e2ac42e1996eff9e1f231753.pdf?index=trueIn PDF document text
    • http://wejajesenopezoj.onlinewebshop.net/rixofakedaganogabo.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE09 5508 bytes
SHA-256: 78cb7a182d78a7ae1dacadfeae5fa58f61ac1546b65110869f95245e46972b5d
font_01_sfnt_off000100bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BD 10888 bytes
SHA-256: 50716ae986912c4a5d2ebe3c2e143487031e8b15a50bbf4597433c3ceea439ff