Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb5a0aaf2e2e5e3d…

MALICIOUS

PDF

39.7 KB Created: 2020-08-17 16:10:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d10ddf6b025f98e880eec86bcc11b8d0 SHA-1: 17744ed5adbcc8eb9d45d4f5a61c06a0dc4a2864 SHA-256: bb5a0aaf2e2e5e3d3524070577da3b12cc5f1fa8f2b0328e53807b9c5b7de026
152 Risk Score

Malware Insights

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

The PDF contains a lure related to a quiz and embeds a large number of external links. One of these links, https://ttraff.ru/pify?keyword=good+old+days+quiz+with+answers, points to a known malicious redirector. The document also functions as a link farm, with many links pointing to PDFs hosted on cdn.shopify.com, suggesting a potential SEO poisoning or content distribution scheme. The ML classifier also strongly indicated maliciousness.

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.ru/pify?keyword=good+old+days+quiz+with+answers
    • http://pajanow.accoladenyc.com/uploads/1/3/2/8/132814930/ed4c00a.pdf
    • http://files.alanaggett.com/uploads/1/3/1/0/131070367/1183821.pdf
    • http://files.strokeofredstudio.com/uploads/1/3/0/8/130873855/xanosetefawuka.pdf
    • https://cdn.shopify.com/s/files/1/0434/5387/4329/files/aftershock_lux_guide.pdf
    • https://cdn.shopify.com/s/files/1/0431/8245/6981/files/6235652514.pdf
    • https://cdn.shopify.com/s/files/1/0433/3076/4968/files/44029051316.pdf
    • https://cdn.shopify.com/s/files/1/0440/6244/1637/files/gudoleriwase.pdf
    • https://cdn.shopify.com/s/files/1/0428/2171/4079/files/rasuvipizipujiwelor.pdf
    • https://cdn.shopify.com/s/files/1/0441/2683/0744/files/hiragana_to_katakana.pdf
    • https://cdn.shopify.com/s/files/1/0427/4031/8375/files/28293067359.pdf
    • https://cdn.shopify.com/s/files/1/0434/7258/4861/files/respiratory_care_exam_review.pdf
    • https://cdn.shopify.com/s/files/1/0432/7433/8472/files/58288987324.pdf
    • https://cdn.shopify.com/s/files/1/0429/8581/6218/files/pakolobavuzewititabuja.pdf
    • https://cdn.shopify.com/s/files/1/0436/0775/2866/files/48835143466.pdf
    • https://cdn.shopify.com/s/files/1/0429/0969/6156/files/52652866245.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005c5d.bin
a9a5f733678c32c3b30f84e91675a7d9efe4fe04135ffc3df64a08ababc69fbb
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C5D 5316 bytes
font_01_sfnt_off00006e8a.bin
611fb48ff84076766a239c360e84799f063646be3972171f2d8ce8a04d5f0bc9
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E8A 10316 bytes