Malicious PDF — malware analysis report

Static analysis result for SHA-256 f50a5eb820338d6c…

MALICIOUS

PDF

43.6 KB Created: 2020-07-31 21:15:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 29330518d1ea68fba86c7d67733e9a76 SHA-1: c0316e78c24eedfa3c05c84629e3f6f6a878d957 SHA-256: f50a5eb820338d6c19a8d60182773a1f54891ab1ea6ffe84c8336b1c7379950c
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a malicious redirector link disguised as an update for Ubuntu command line, which is a common social engineering tactic. The ML classifier strongly flagged this PDF as malicious. The document body contains obfuscated text and the malicious URL, indicating an attempt to deliver a payload or redirect the user to a phishing 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.ru/pify?keyword=update+ubuntu+command+line
    • http://files.filipemiguelart.com/uploads/1/3/1/6/131606094/1bd4509c93c4d.pdf
    • http://files.fanitra.com/uploads/1/3/0/8/130813644/lasunuvifufix-xurujilifu.pdf
    • http://files.foundantiquesde.com/uploads/1/3/0/7/130739239/bonikowogaxunaw_fivegadivok.pdf
    • http://files.bemisnursery.com/uploads/1/3/0/8/130813841/6102928.pdf
    • https://cdn.shopify.com/s/files/1/0435/7101/9935/files/93587526477.pdf
    • https://cdn.shopify.com/s/files/1/0432/2613/6743/files/potedijomedoj.pdf
    • https://cdn.shopify.com/s/files/1/0428/5526/8519/files/zukujabalugaduvus.pdf
    • https://cdn.shopify.com/s/files/1/0434/7366/6213/files/35331307850.pdf
    • https://cdn.shopify.com/s/files/1/0428/6831/0172/files/rajabisezu.pdf
    • https://cdn.shopify.com/s/files/1/0431/9064/8996/files/jinipamosetafo.pdf
    • https://cdn.shopify.com/s/files/1/0427/7973/8278/files/zibupuluxugugikikekesesef.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/71062637782.pdf
    • https://cdn.shopify.com/s/files/1/0432/4484/7261/files/33205185751.pdf
    • https://cdn.shopify.com/s/files/1/0429/8365/3535/files/44660183394.pdf
    • https://cdn.shopify.com/s/files/1/0439/5591/2862/files/21462957121.pdf
    • https://cdn.shopify.com/s/files/1/0431/1570/8573/files/zavuwumojepakijub.pdf
    • https://cdn.shopify.com/s/files/1/0430/2451/5235/files/27711353216.pdf
    • https://cdn.shopify.com/s/files/1/0427/9818/6652/files/74820988589.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_off00006c79.bin
1165a31eccf4a38af7e01acc9210f28ab8df5c462ec61ba6be2673f3c5d784c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C79 5076 bytes
font_01_sfnt_off00007dae.bin
a775acf3077644aff826ab706a92100223bff0612ffcbf8861457aab8417172b
pdf-font-stream PDF embedded font (sfnt) at offset 0x7DAE 10356 bytes