Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a8bdf137664bb34…

MALICIOUS

PDF

49.1 KB Created: 2020-06-06 02:18:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 4f779b9b50eb331e950ab41155686de5 SHA-1: 7ec390e9ebabdad4ad815810bf2c57edc8601d0a SHA-256: 2a8bdf137664bb3462772c1b058723e0589a5a065d391460da4ffc23443c0697
136 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to other PDF files hosted on similar domains. One of the embedded links, 'http://gyrtn.bpmtc.com/uploads/1/3/0/7/130775685/130775685.html#mp3+birle%25C5%259Ftirme+program%25C4%25B1+indir+gezginler', suggests a lure for downloading MP3 software. The heuristic 'PDF_SEO_LINK_FARM' indicates a technique to generate traffic or distribute content through a network of linked PDFs. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://gyrtn.bpmtc.com/uploads/1/3/0/7/130775685/130775685.html#mp3+birle%25C5%259Ftirme+program%25C4%25B1+indir+gezginler PDF link annotation
    • http://hostmaster.swlondonrenovations.co.uk/uploads/1/3/0/5/130551086/dikeluvufo.pdfIn PDF document text
    • http://emmachristopherlakesassociation.org/uploads/1/3/0/2/130272940/2219734.pdfIn PDF document text
    • http://dimension-net.net/uploads/1/3/1/4/131436983/gofax-mukagarepilube-keperib-zokiwup.pdfIn PDF document text
    • http://mywisemoney.net/uploads/1/3/0/4/130436313/8d94087558e.pdfIn PDF document text
    • http://autodiscover.rbpaintcompany.com/uploads/1/3/1/3/131380205/kixavit.pdfIn PDF document text
    • http://pagosakayakrentals.com/uploads/1/3/0/3/130313524/jutodi.pdfIn PDF document text
    • http://gyrtn.bpmtc.com/uploads/1/3/0/7/130775685/terms.htmlIn PDF document text
    • http://gyrtn.bpmtc.com/uploads/1/3/0/7/130775685/dmca.htmlIn PDF document text
    • http://gyrtn.bpmtc.com/uploads/1/3/0/7/130775685/policy.htmlIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://tomejaz.files.wordpress.com/2020/06/18113198864.pdfIn PDF document text
    • https://pikirumabe.files.wordpress.com/2020/06/zegasojewefofofufekuv.pdfIn PDF document text
    • https://zozumak.files.wordpress.com/2020/06/89364293540.pdfIn PDF document text
    • https://sezagadi.files.wordpress.com/2020/06/tidakoju.pdfIn PDF document text
    • https://vikijoxedip.files.wordpress.com/2020/06/16277297580.pdfIn PDF document text
    • https://juguxog386085692.files.wordpress.com/2020/06/wuxobunifakege.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005a15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5A15 6588 bytes
SHA-256: fa72874b8c381873b432d3b5cea9ecddba20f04e8e1c9face7d560df1136061a
font_01_sfnt_off00006a83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6A83 3092 bytes
SHA-256: d087c77bd37db199d2ba3f3d4bbe0ecf5553f3a120c395f7280997d911ad18dd
font_02_sfnt_off00007764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7764 12688 bytes
SHA-256: 6568a97411fd828df2f8e3a0f9bedb5c0e700f2b7ec1031b826a05a3ba02d8bf
font_03_sfnt_off00009ef1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9EF1 16492 bytes
SHA-256: 17683c212d38ed0b001e01407b1db7150c7f0ac11484a74e1d06e51444ce6a5e