Malicious PDF — malware analysis report

Static analysis result for SHA-256 13cbbc82829249f7…

MALICIOUS

PDF

82.0 KB Created: 2021-09-19 08:22:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5926e738639b1bbb35654360ff5ad2fa SHA-1: 9c8903c0814990d3e5404a568b8a32678b23e062 SHA-256: 13cbbc82829249f76723807c6e49b01939ac641c003cb980bc19fc1f482bf55b
144 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a significant number of external links, many pointing to compromised CMS upload directories or disposable hosting. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to download an archive, which is often used to bypass gateway security. The ML classifier strongly suggests malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://crysiq.ru/uplcv?utm_term=m+for+alphabet+words
    • http://vvk-wiedermann.at/userfiles/file/19598290586.pdf
    • https://aczv.fr/userfiles/file/nozodesuberejidi.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f76c9cc875---jatupolakiriburowu.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebc93d9f47---lufupewe.pdf
    • http://multiflex.ru/userfiles/file/radonijozikigiwevewowam.pdf
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/gowusagerujepidorur.pdf
    • http://jongauger.com/ckfinder/userfiles/files/dojopatejides.pdf
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/30008008702.pdf
    • http://dlzhrjd.com/images/uploadfile/files/gimivego.pdf
    • http://helderlive.nl/ckfinder/userfiles/files/50100015551.pdf
    • http://lblussana.it/images/file/7638963057.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c407db93d2---simajoloropexeser.pdf
    • http://incomingmakedonia.com/files/files/44119233687.pdf
    • http://logicamail.it/draft/media/merofiwikimejebadataf.pdf
    • https://fallsplat.se/bildbank/file/dudik.pdf
    • http://bsa-billiard.by/images_from_html_editor/file/lofiwiwamotazizasuru.pdf
    • https://elminhaj.org/userfiles/file/91471583692.pdf
    • https://sthouseluxury.com/upload/files/64436338599.pdf
    • https://chuyennhakienvangvn.net/upload/files/90193099878.pdf
    • http://vonschickenconcord.com/uploads/files/zulufavafiwufiwigiviko.pdf
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/39861139765.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/7b816dacd79cb7c2f1731c020dd61f5e/24437663047.pdf
    • http://carscaso.com/js/upload/files/52368827587.pdf
    • http://laptopplus.be/app/webroot/files/userfiles/files/84672615761.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/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da32.bin
fa29af5c59d354254b89e03dc34357260a622b58631f620c92a1eac922767196
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA32 10620 bytes
font_01_sfnt_off0000f278.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF278 16792 bytes
font_02_sfnt_off00010a8a.bin
c2269ed44b4cfa5745cbbfd509dac72a374256d9feadae2f69fb5e8fc98c3de4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A8A 18520 bytes