Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b07c13f8f9c26d5…

MALICIOUS

PDF

53.0 KB Created: 2020-08-18 20:17:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 63ea3b722230a421770f9aad20958f99 SHA-1: c81b24bb65b2d11597661788b006ba12be229820 SHA-256: 6b07c13f8f9c26d574b49b4cd961bac517e63a9003a3cab7e1fcb2f207b5dfc7
154 Risk Score

Malware Insights

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

The PDF contains a lure for 'expense sheets template free' which redirects to a malicious redirector. This redirector then leads to a link farm of 13 PDF files, many hosted on Shopify. The ML classifier strongly indicated maliciousness, and the presence of multiple external links suggests an attempt to distribute further malicious content or phish users. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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.com/pify?keyword=expense+sheets+template+free
    • http://nufepesiv.shivanirustagi.com/uploads/1/3/0/8/130873825/3c0c885f6.pdf
    • http://zoguj.smalltalk-maadi.com/uploads/1/3/1/3/131384284/8711a8f.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0447/6397/1733/files/10934530163.pdf
    • https://cdn.shopify.com/s/files/1/0435/3350/0565/files/72504938079.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/pawatofamilafal.pdf
    • https://cdn.shopify.com/s/files/1/0431/6682/6656/files/risotuki.pdf
    • https://cdn.shopify.com/s/files/1/0430/7664/9124/files/85636265660.pdf
    • https://cdn.shopify.com/s/files/1/0432/7673/0533/files/44174844430.pdf
    • https://cdn.shopify.com/s/files/1/0434/6186/9733/files/sovutezajisamapak.pdf
    • https://cdn.shopify.com/s/files/1/0437/6464/6042/files/69063907065.pdf
    • https://cdn.shopify.com/s/files/1/0433/0212/5733/files/arm_microcontroller_lpc2148_datasheet.pdf
    • https://cdn.shopify.com/s/files/1/0438/6881/5528/files/skyrim_special_edition_nude_mod.pdf
    • https://cdn.shopify.com/s/files/1/0431/0587/8173/files/xemulipovezukilebibupowiw.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_off000091f5.bin
290d35591aef62444c1f369f7b70e8d4d1f4c0f84c0a4c5b03f301ee507b5156
pdf-font-stream PDF embedded font (sfnt) at offset 0x91F5 5164 bytes
font_01_sfnt_off0000a35c.bin
75ff75c3daf362db1994b3f721aeef48a8f6d67269fce23ac7653190e54dfec0
pdf-font-stream PDF embedded font (sfnt) at offset 0xA35C 10416 bytes