Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8d214c180c68dbb…

MALICIOUS

PDF

71.0 KB Created: 2021-09-27 13:53:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 056766a90d374045f9d42dcc7f3ca517 SHA-1: a4a330c1db5e86de414a33210b2960682d12eb84 SHA-256: a8d214c180c68dbb3f529e2ebc902a94326fabcf72808881e211a7b04ca1791a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm pointing to numerous URLs, many of which are hosted on compromised CMS uploads or disposable domains. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the structure and URL distribution suggest an attempt to lure users to external sites, potentially for further exploitation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.horakgolf.cz/ckfinder/userfiles/files/97766682011.pdf In PDF document text
    • http://summitremodelinginc.com/userfiles/files/74713116025.pdfIn PDF document text
    • http://kbfrutos.sk/images/_file/kilunitok.pdfIn PDF document text
    • https://concurs-euclid.ro/upload/fck/81122692748.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/161315b3d742e3---66364301935.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/madijesedebipogososib.pdfIn PDF document text
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50441210844.pdfIn PDF document text
    • https://www.e-oswiata.olesnica.pl/ckfinder/userfiles/files/54883345788.pdfIn PDF document text
    • http://rioairporttransfer.com/ckfinder/userfiles/files/27949162555.pdfIn PDF document text
    • http://minipit.com/data/files/46574145397.pdfIn PDF document text
    • http://zuszdounky.cz/files/kunemazizumunubexazipen.pdfIn PDF document text
    • http://abakus-routing.co.uk/ckfinder/userfiles/files/rikarirofipo.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tutaro.pdfIn PDF document text
    • http://sartoriaventurini.com/userfiles/files/xakajovizet.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/43400525296.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/64901778529.pdfIn PDF document text
    • http://parateam.cz/file/zobonef.pdfIn PDF document text
    • http://nhahanghienminh68.com/upload/files/95566065085.pdfIn PDF document text
    • https://qatarsecurityservices.com/public_html/userfiles/file/mapivisowufowuzeragobut.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613d267d234e0---pobopamamanetaxal.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/semonodedazikul.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/iftupqihr4pavp72u504t284io/20314315262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=bad+piggies+hack+apkPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/daxewinunarojopeko.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b17f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB17F 10468 bytes
SHA-256: cd26b17030951726fa45c7113fc5db36d258994d540324661d79cb3b757c070f
font_01_sfnt_off0000c937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC937 17196 bytes
SHA-256: 3bd8f181764a6c64bd12070bd78af79143521013ce92e4987d01c28c92c8818b
font_02_sfnt_off0000f531.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF531 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1