Malicious PDF — malware analysis report

Static analysis result for SHA-256 81c627b21e1757ff…

MALICIOUS

PDF

51.4 KB Created: 2020-07-27 08:06:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b400e0ab205b47a1c3b9f264aa40f54c SHA-1: 898ed96242715343997871db9b8540b25044a380 SHA-256: 81c627b21e1757ff7a631be6056fa6fdd59d15b5bb4365e26853d15760ab7bc3
162 Risk Score

Malware Insights

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

The PDF contains numerous links, with one identified as a known malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external PDF links, suggesting an attempt to manipulate search engine results or distribute further malicious content. The presence of a 'download button' lure reinforces the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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
  • 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://ttraff.ru/pify?keyword=template+for+web+design+psd
    • http://files.wvangler.com/uploads/1/3/2/6/132681586/fibudatib.pdf
    • http://files.mindfullifefocuscommunity.com/uploads/1/3/0/7/130740443/9590386.pdf
    • http://files.chelseagouldnp.com/uploads/1/3/0/7/130739780/bupivofubekide.pdf
    • http://files.mortgagematchmaking.com/uploads/1/3/0/8/130813427/fb8d7fb09.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/5442/3464/files/buvadekix.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/88075317933.pdf
    • https://cdn.shopify.com/s/files/1/0435/3182/9412/files/vodamomasada.pdf
    • https://cdn.shopify.com/s/files/1/0429/7054/6329/files/fokuvatofewenajuro.pdf
    • https://cdn.shopify.com/s/files/1/0431/9471/2228/files/93557747874.pdf
    • https://cdn.shopify.com/s/files/1/0433/5032/7451/files/6459478214.pdf
    • https://cdn.shopify.com/s/files/1/0431/1423/4016/files/baganivewom.pdf
    • https://cdn.shopify.com/s/files/1/0429/9482/7418/files/xodudotewiwipiwokuja.pdf
    • https://cdn.shopify.com/s/files/1/0434/9624/3364/files/mapewujusinolivokekujodi.pdf
    • https://cdn.shopify.com/s/files/1/0431/7744/3483/files/89813640148.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00008b27.bin
1009f1f47080fe5fd9cc68ad81778207bbc2a16d8873bb791878143d2bfd412a
pdf-font-stream PDF embedded font (sfnt) at offset 0x8B27 5328 bytes
font_01_sfnt_off00009d3a.bin
ace92d9c113238fbb2b7002cb6d5920377883f77c6784c63f7a0475672fccc5e
pdf-font-stream PDF embedded font (sfnt) at offset 0x9D3A 10388 bytes