Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c2406a2e3dc2dd0…

MALICIOUS

PDF

87.9 KB Created: 2021-06-27 07:52:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e55e9c94bf109b828380a5a24df82477 SHA-1: 786786cf03dd32061059bdd3ffaefdbe97828b4a SHA-256: 8c2406a2e3dc2dd0f49abeadd50d4b31b760e951ff8ff1197568aa5a4fd523f7
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of embedded URLs and the nature of the heuristics point towards an attempt to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/nuf7eutftmpaviatlelbqsjtqk/76524653471.pdf
    • http://busanpc1.com/upload/fckeditor/file/89075575288.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd8c33cc7a8---jiwutivibale.pdf
    • http://angelojrobles.com/admin_initial_test/userfiles/file/lasibaxa.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160ac671f53806---12075617837.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/0r2htp2t47mlprkmctcm7bpboe/siluxabogadi.pdf
    • https://orldoc.ch/wp-content/plugins/super-forms/uploads/php/files/p4bu8i4oc6rui9tjf5cl1alo33/pewunanevovamapiwag.pdf
    • http://www.huntsvillepr.com/files/files/fomiserefub.pdf
    • http://artistalexanderkanevskyroyalshakespeareglobetheatrelondon.com/clientMedia/file/miguwapude.pdf
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608f6c148ac37---61032084022.pdf
    • https://srldirect.com/ckfinder/userfiles/files/pezonepoxano.pdf
    • https://irisapp.cn/uploadfiles/fckeditor/20210605/file/16228654772416.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/bf16b8d6c7629adeaba30e313e3d0638/vunizilifeku.pdf
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/j1d5iccut1p0qog8uaef5a1362/xufewabawimojilirumen.pdf
    • https://ottenburger.com/userfiles/file/nobilukaneno.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609635d1d061d.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/c2dbde0d8d09b4abf30697ad1d5474f3/8947248366.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/3fiv03octdts8s7cd3jv08jfk0/70527588649.pdf
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/826dc0ca5b0f62d26023caa7e1825d34/94130871261.pdf
    • http://ongnuocdenhat.com/upload/files/53074308662.pdf
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/7be52e47915e15a7057c094f27d3c52d/denerirevexurufeviteve.pdf
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/fcf376abfc04c276baadb2acdfa8375a/somebaxi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=the+scarlet+letter+grammar+and+style+answers
    • http://irodori.kir.jp/files/file/vuxuzimisadama.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_off0000f408.bin
c84cb3fc245939570b0644fd81e59c9845ba86803e55bec805f409fb966cf2ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xF408 17520 bytes
font_01_sfnt_off00012189.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12189 16792 bytes
font_02_sfnt_off000139a0.bin
f7b7e31d79268e6b95ae2368dacd5f52e33d0ba55440e7c46aed557f7538d2a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x139A0 10768 bytes