Malicious PDF — malware analysis report

Static analysis result for SHA-256 a12cfd7820356936…

MALICIOUS

PDF

62.6 KB Created: 2020-08-15 02:40:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ef4e77d43c3df28d1aac21195406fa6a SHA-1: 6b979c74ec789d700bc9ef039deac242a97e44ae SHA-256: a12cfd7820356936a921781deca1440b0e1e9df1a0d2ac30898bca3c78cd291a
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to ttraff.com. The document body, though heavily obfuscated, contains text and URLs related to 'free download pdf reader for laptop', reinforcing the lure. The ML classifier also strongly indicated maliciousness. The primary IOC is the redirector URL, which is likely used to host further malicious content or phishing pages.

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/wb?keyword=free%20download%20pdf%20reader%20for%20laptop
    • http://files.millermiller.info/uploads/1/3/1/6/131606366/2503eb40a69.pdf
    • http://files.janesmithacu.co.uk/uploads/1/3/0/7/130740251/212888.pdf
    • https://cdn.shopify.com/s/files/1/0438/6160/6550/files/xadiworikedizat.pdf
    • https://cdn.shopify.com/s/files/1/0430/1262/0447/files/93843527365.pdf
    • https://cdn.shopify.com/s/files/1/0428/5631/7091/files/22340157334.pdf
    • https://cdn.shopify.com/s/files/1/0433/3489/3721/files/nuwolisogida.pdf
    • https://cdn.shopify.com/s/files/1/0428/8207/2743/files/12544897142.pdf
    • https://cdn.shopify.com/s/files/1/0435/3972/6487/files/jeevan_amar_proposal_form_511_download.pdf
    • https://cdn.shopify.com/s/files/1/0429/9191/1066/files/sum_in_r.pdf
    • https://cdn.shopify.com/s/files/1/0435/6443/3569/files/12002492761.pdf
    • https://cdn.shopify.com/s/files/1/0435/4703/3752/files/32013404737.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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005dbb.bin
1c28c3cbe3927ea9daa6e5dd8495d9a67b533c66f6ccbe6517dc95b3fac79d26
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DBB 30632 bytes
font_01_sfnt_off0000baef.bin
4d80ca7ca73f9c4206485b71e1c3951af0c615505d11e2dbc9d1ead2051d42f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xBAEF 4904 bytes
font_02_sfnt_off0000cbc0.bin
6061a01ae9786a081ad59fe9da9ada479ee6790d3973889f43d087aa6158b56d
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC0 9848 bytes