Malicious PDF — malware analysis report

Static analysis result for SHA-256 355b9fbdadde26d5…

MALICIOUS

PDF

74.7 KB Created: 2021-07-01 18:05:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2d18c18a3f38bd5a85a7e5e45d405fe0 SHA-1: a0b6a13c75c0df6446aea7c04ec0a94ef29594df SHA-256: 355b9fbdadde26d5dfeda4cafe67b2cb0aaf9e659a57e8bcefa4da4ed817a082
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress upload directories and other disposable hosting sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of multiple external URIs and compromised CMS upload links suggests an attempt to leverage these to host or distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • 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 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://3qbuy.com/CKEdit/upload/files/45214789756.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/de959cb623b33cfd11a1ded4e06eca83/87420016929.pdf
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/61a94fbf77eb4ea91255d88872fcb96c/95050413018.pdf
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/o2o40chvhmj364di16ejgrsbg2/musikewepop.pdf
    • http://bigpictureresources.com/userfilesbigpicture/file/jazujopel.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/5d7d9ff2cdcfc80e0ffa2249b5c8bb81/kanuzepakamil.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/3jo5vheij8q20cmbuiktquq7d0/21094983294.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/lk1du74n4hm0ph34qge98acuc4/zurivoxatoxipis.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/v25a99ft6cii9hstarkqrn42b0/lofepofal.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090396c27568---55467578799.pdf
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/2a006e6b6a72c1c6b94a610f97aa36be/nafusasotetak.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/075b28fffd1512d5de4b6363f358b8a2/wuzafefakifunafalaxev.pdf
    • http://ohana1bbq.com/uploads/files/76997917088.pdf
    • http://firegallery.ru/img/upload/vusanalekizelirebadi.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085fb6b4e9b7---wigagafekadazobogun.pdf
    • http://aep-tc.com/cache/fck_files/file/sotab.pdf
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160862fe6930d0---womizemupabejapaso.pdf
    • http://sgo-bage.com/public/files/files/19519736783.pdf
    • https://abugfreemind.com/userfiles/file/jodedesegib.pdf
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/2shsm6elk76045kca7ihd8jajp/37524132625.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/4ddd253spmu1s8nilj3i5hbf9o/51010224999.pdf
    • https://777mto.info/contents//files/49821787281.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=databases+illuminated+solutions+manual
    • 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_off0000c043.bin
ef4b7f0856db198e3e4795e1045b3b138445e16bfcbf3755ee37563c7ad45d82
pdf-font-stream PDF embedded font (sfnt) at offset 0xC043 10548 bytes
font_01_sfnt_off0000d84b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD84B 16792 bytes
font_02_sfnt_off0000f05d.bin
7bcf0cd854c82222b2c9d0134d95f3266917bc89dc39d435ce4998bb20677eea
pdf-font-stream PDF embedded font (sfnt) at offset 0xF05D 16740 bytes