Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c528435458aeba1…

MALICIOUS

PDF

106.2 KB Created: 2021-06-25 20:38:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 14054cb2545947e565a5b7857757ae6a SHA-1: e3d848c21a2c4ecbc733c53bf053e0ad78262cf0 SHA-256: 1c528435458aeba197d3d4d5d8206606eb2a542a11a9c3824612be610c620415
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm for SEO manipulation or malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://chcial.ru/uplcv?utm_term=african+american+museum
    • http://myjobcareer.net/userfiles/file/2021061910300773499.pdf
    • http://slsnn.ru/content/file/51393122596.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/16071a17d7cec7---wazemubulubovusinedaw.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2b8b240030---bilasubav.pdf
    • http://anhuizhkj.com/upload_fck/file/2021-5-3/20210503093227843775.pdf
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/8eqve85n2mv13r13goi93vt6s1/bejuwuke.pdf
    • http://princeworldwide.com/multimedia/userfiles/file/42093677386.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160c4c84f304b9---44379703119.pdf
    • https://zlatartopalovic.rs//files/36848607357.pdf
    • http://www.derbysignandgraphics.com/uploads/file/20284608480.pdf
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160a4cf8a9bfca---xafedadakovanexit.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/ma4nfndl5kun4nbiv525thp2lc/nimet.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b57eb40abb1---rexirize.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1609ae35bf325f---92264914045.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf96f102b18---saxazip.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d609c236b---74537580572.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/1tr41vk52289i5b12e905n40g7/68903748547.pdf
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/1031c86e93d292720002b43ef3d2163b/pogometowesepisomine.pdf
    • https://cgeminfos.ma/upload/file/jeser.pdf
    • http://almar-bus.pl/userfiles/file/82629060311.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/5eb4cd5b0677f0e6264e6c201b7da28e/kuwumazewelox.pdf
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/c20178797e06c63d800e3957b0746fd5/vitogatikisutadepup.pdf
    • http://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/sovuge.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_off00013ee7.bin
2e5367f82d4feb145d8be0dd2d39bf177460983ef04d9f9c12f994198d494b4b
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EE7 17432 bytes
font_01_sfnt_off00016ca3.bin
6e806eff39e98d79c0af93eaa866f228b09c021e9573d2f79b94bd4f549d5197
pdf-font-stream PDF embedded font (sfnt) at offset 0x16CA3 10312 bytes
font_02_sfnt_off000183d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x183D6 16792 bytes