Malicious PDF — malware analysis report

Static analysis result for SHA-256 53761001bf1617bf…

MALICIOUS

PDF

83.3 KB Created: 2021-08-17 22:19:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bd466cd9a359efcb47419889599d7789 SHA-1: c8e480dd45efb27f7a062ac4831747d13e83dac8 SHA-256: 53761001bf1617bf655a7b756a776c8d217056baddd61b37ebfea47bf8aadd8d
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features numerous links, including one pointing to a compromised WordPress upload directory, suggesting an attempt to redirect users to malicious content or download further stages. The ML classifier strongly indicates malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://stl-log.com/htdocs/cljr/data/files/zekepawopurunozusom.pdf In PDF document text
    • https://digireg.es/upload/27227012200.pdfIn PDF document text
    • http://kaies.cn/upfiles/210602175350383434isn4tz.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160706bc3a8e82---suzodevodenunalud.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/wazerezelezinonebagevad.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/4aqnmo5h0ksk0m8snst6e6hpd1/93059212618.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/wokokakadelige.pdfIn PDF document text
    • http://nensi.si/upload/file/jutofekovaj.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b218e58fd0c---89013319748.pdfIn PDF document text
    • http://codefon.hu/js/ckfinder/userfiles/files/28520290395.pdfIn PDF document text
    • http://hondasushi.com/uploads/files/gozuxalefezaninarujuk.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6393ca7c6---zedujap.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/nosaxogejimetezu.pdfIn PDF document text
    • http://security-m.jp/tool/images/file/84570126986.pdfIn PDF document text
    • https://uniqrelation.com/userfiles/file/mexitufodi.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/nrv8bg3p42uj9e1g17tnd4c7u7/dovemujoramaxejif.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/992682c5c5f592f78e84bc062db98755/4983480879.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/gebipegepazazovewulir.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d01562b451---8788752372.pdfIn PDF document text
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/62663f3bf2b0942abbf1f9685f87dfe4/40891096690.pdfIn PDF document text
    • https://gw21.ch/uploads/userfiles/file/60836132741.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=epilepsy+pdf+2019PDF link annotation
    • 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_off0000e474.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE474 10464 bytes
SHA-256: ea91160bf3384aabae1f14a0f305c91f2d9b0b038212a6aac1981f7a93648f0d
font_01_sfnt_off0000fc66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11478 16808 bytes
SHA-256: b6596a537946cf187ae99358b49effa3d0ea661c105cfed50f758631843d58eb