Malicious PDF — malware analysis report

Static analysis result for SHA-256 99dad68e3adb3694…

MALICIOUS

PDF

38.4 KB Created: 2020-08-07 01:06:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 196694feb04991dc9615bca390e8a491 SHA-1: 7b839596c2c7f809f842ec2faf7aaf8d6e7fee8e SHA-256: 99dad68e3adb36942d1f4dcf82a098e15b7225e26e0eb88f9e9789a8b83427ee
152 Risk Score

Malware Insights

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

The PDF was flagged by a critical heuristic for linking to known malicious redirector infrastructure. Additionally, it contains a large number of external PDF links, many hosted on Shopify, suggesting a link farm or SEO manipulation tactic. The ML classifier also strongly indicated maliciousness. The primary malicious IOC is the redirector URL, which is likely used to funnel users to a malicious site.

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=physical+science+grade+11+text+book+pdf
    • http://rerek.opendoorsspokane.com/uploads/1/3/1/4/131453540/josevado-zelikoraxel.pdf
    • http://files.charlottecrone.com/uploads/1/3/1/8/131871621/8099088.pdf
    • http://files.boyertownareamulti-service.org/uploads/1/3/2/7/132740619/af77c51.pdf
    • https://cdn.shopify.com/s/files/1/0430/7881/1797/files/rizatafemolexapu.pdf
    • https://cdn.shopify.com/s/files/1/0438/4571/4077/files/calcium_gluconate_davis.pdf
    • https://cdn.shopify.com/s/files/1/0435/8062/0963/files/little_league_baseball_rules.pdf
    • https://cdn.shopify.com/s/files/1/0431/6289/4485/files/mikumowuxarebutatexoxu.pdf
    • https://cdn.shopify.com/s/files/1/0449/4472/0040/files/marketing_strategy_definition.pdf
    • https://cdn.shopify.com/s/files/1/0437/5547/1002/files/edema_paru_adalah.pdf
    • https://cdn.shopify.com/s/files/1/0431/3173/2125/files/netulojifired.pdf
    • https://cdn.shopify.com/s/files/1/0431/6997/2392/files/monatifebebivaj.pdf
    • https://cdn.shopify.com/s/files/1/0435/3074/8055/files/kutugi.pdf
    • https://cdn.shopify.com/s/files/1/0437/7346/0641/files/9800242408.pdf
    • https://cdn.shopify.com/s/files/1/0438/1478/1085/files/57746542114.pdf
    • https://cdn.shopify.com/s/files/1/0432/7522/3200/files/zugiwegowezudoketipev.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/28603075132.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_off00005540.bin
6de7efaef980ccc5a49226670d4cf618749e0ef4a3ff859f6be6c9ea4fb0d06e
pdf-font-stream PDF embedded font (sfnt) at offset 0x5540 5844 bytes
font_01_sfnt_off00006931.bin
cd1852bebcc1059275634c59e72bf0da03ab1d76214d2c371b1871836a7a57d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x6931 9744 bytes